Sciencemadness Discussion Board - bitter almond benzaldehyde

bitter almond benzaldehyde

paccman278 - 2-12-2004 at 04:51

anyone ever xtract benzaldehyde from bitter almond extract? swip has been searching the net for a week now and cant find a bulk amount of the almond, any one know a name of a brand or company that has it in bulk. swip knows how to make it from oxidation of toluene but is looking for a less time consuming way. thanks for saving swip from yet another headache

Organikum - 2-12-2004 at 08:45

Benzaldehyde is a list I chemical and watched. If you cannot get oil of bitter almonds locally OTC, I wouldnt recommend to order it from anywhere.

The purification depends on
- the oil, often alcohol and other stuff is added
- what you need it for, different reactions demand different grades of purity, or tolerate certain impurities or not.

Thermal - 2-12-2004 at 09:21

I agree with Organikum. You shouldn't try to order "bitter almond oil" or any pure (high %) benzaldehyde product which is sometimes marketed as an "almond" product from anyone, as it is indeed closely watched.

However some retail bottles of synthetic "bitter almond extract" for food flavoring from one of those not-quite-third-world countries contain upwards of 30% benzaldehyde. +water&alcohol
Seperation would be simply by distillation.

YMMV

[Edited on 10-18-2006 by Polverone]

Mendeleev - 2-12-2004 at 15:19

Order cassia(cinnamon) oil instead, refluxing cassia oil with a solution of potassium carbonate gives benzaldehyde in fairly high yields. US Patent 4,716,249 gives this procedure:

EXAMPLE II

Preparation of Natural Cinnamaldehyde and Natural Benzaldehyde

Reaction: ##STR47##

Into a three neck flask equipped with stirrer, thermometer and reflux condenser is placed 10 grams of cassia oil and 100 ml of a 3% aqueous sodium carbonate solution. Boiling chips are added and a water-washed stream of nitrogen is passed over the reaction mass to help prevent oxidation of the formed benzaldehyde. The mixture is heated to reflux and refluxed for a period of 7 hours (100.degree. C.). The resulting material contains 70% benzaldehyde and 30% cinnamaldehyde.

There is another US patent, 4,673,766, which gives a similar procedure that uses cassia oil. I got those two patents from the hive, which is unfortunately down

. Search the net for "cassia oil" and "bulk" and you should find what you're looking for. I found a supplier where I can get 2 L for about $50 which should yield around 1 - 1.5 L of benzaldehyde. As far as almond oil goes, I wouldn't try it, and the crappy 1 oz of bitter almond oil at the grocery store containing around 20% benzaldehyde for $2.00 is a rip-off . You could also look into synthesizing it by MnO2 oxidation of toluene, and hydrolysis of benzal chloride, which can be easily synthesized.

[Edited on 2-12-2004 by Mendeleev]

paccman278 - 3-12-2004 at 02:04

yeah swip thought so, he knew benzaldehyde was a list 1, here in so. cal you could buy the bitter almond but not by the bulk although he found a few companies that sell it by the gal. benzalhyde content unknown. swip will go back to the oxidation of tolu. just got tired of chlorine. thanks guys

Mendeleev - 29-12-2004 at 20:05

You know what, fuck the DEA, benzaldehyde is restricted, but they can't regulate an essential oil in my opinion. At least I don't think bitter almond oil would actually be considered a LIST 1 chemical since it isn't pure benzaldehyde. So even if it is watched, they can't do anything about it legally. If they get on you about it you can tell them to piss off since it isn't a chem supplier but an aromatherapy store.

[Edited on 30-12-2004 by Mendeleev]

Thermal - 29-12-2004 at 21:47

Well if you want to play russian roulette, go right ahead and order a truckload of the stuff.

You can tell the DEA to go fuck all you want, right up untill they decide to show up at your door at 5am.

Of course ordering a reasonably small quantity of "synthetic almond extract" is rather unlikely to provoke such a response, but it's worth being aware that its possible for you to be put on a watch list.

You need to ask yourself - is it worth the risk? Perhaps.
But they're sneaky bastards.
They can and they do regulate anything they want.
See the recent busts involving controlled delivery of certian other essential oils.

The days of mailordering gallons of potential drug precursors without serious threat of problems are over and I'm not afraid to say so.

[Edited on 30-12-2004 by Thermal]

Mendeleev - 29-12-2004 at 22:07

What recent busts involving controlled delivery of oils? And anyway they have no legal grounds to do anything. They can watch all they like, they can't do shit because bitter almond oil does not appear in any of their scheduling actions.

EDIT: I happen to be russian

.

[Edited on 30-12-2004 by Mendeleev]

Rosco Bodine - 29-12-2004 at 22:57

Benzyl alcohol is sold by the gallon as a solvent for artists and bookbinders artwork restorers , and it should be easy enough to convert to benzaldeyde , probably more cheaply than an essential oil . IIRC , either HCl or Cl can convert the alcohol to the chloride and then that reacted with hexamine gives the aldehyde . Damn , is this place turning into a dope cookers convention ????

Mendeleev - 30-12-2004 at 08:56

Yeah, when the hive went down they all fled here. Benzaldehyde is not really a dope chemical exclusively. It's kind of sad it's a list I it's got so many other uses.

the "lazy-ghetto" way

Polverone - 25-1-2005 at 23:54

I wanted a small amount of benzaldehyde to try making bisulfite adduct with. So I grabbed from the kitchen a bottle containing "water, 36% alcohol, and benzaldehyde" (the usual artificial flavoring stuff) and saturated some of the liquid with table salt in a large test tube. Then I extracted by shaking it several times with unrefined automotive starting fluid and pipetting off the top layer. This top layer gave a thick mass of white, flocculent adduct when shaken with an alcoholic bisulfite solution made according to Vogel and left to stand for several minutes. Yield of adduct was not determined by weighing because I did not want to dry it. Half the portion of adduct was filtered then while still wet shaken with sodium carbonate solution in a smaller test tube to give a visibly distinct and heavenly-smelling layer of benzaldehyde on top of the aqueous solution. If you're not interested in the behavior of bisulfite adducts, the starting fluid can simply be evaporated away to give fairly pure benzaldehyde, though if done in open air you may well lose much of the aldehyde to oxidation.

This would be a very expensive way to get benzaldehyde if you rely on the usual supermarket flavorings, but I've seen inexpensive containers of up to 300 ml artificial almond flavor at stores that target restaurant-scale customers. And of course the small Lorann Oils containers of pure benzaldehyde ("almond oil"

are also available OTC at specialty cake/candy places. If you need more than 100 grams or so, though, I think the cassia oil method looks much more attractive.

conducter - 7-10-2006 at 01:40

hey polverone, swim had been wondering the exact same way to extract the aldehyde from local grocery store artificial almond extract.

If swim didnt want to distill and didnt care about yields, would there be a way to evap the ether without overoxidizing the benzaldehyde? Maybe on very low heat and as soon as the ether is gone wash the benzaldehyde with water/sodium carbonate solution and then store in sealed container?

Also there is a very popular site, not an auctioning site that is selling Lorann Gourmet Brand Bitter Almond Artificial Flavouring, now from what ive read this should be highly concentrated Benzaldehyde and with a wash should be usable as is?

[Edited on 7-10-2006 by conducter]

Polverone - 7-10-2006 at 10:23

None of this 'swim' business here, please. I would guess the fastest way to remove ether would be under vacuum, and with that you shouldn't need any heat. If you did want to heat, maybe a small amount of BHT preservative or hydroquinone would minimize oxidation. Lorann bitter almond flavor oil is pure benzaldehyde.

prole - 7-10-2006 at 17:30

I often order essential oils from a wholesaler out of the pacific northwest, because I make soap to sell at local farmers markets and art shows. Only legitamate oils, mind you, but noticed their policy on oils like brazilian sassafrass and bitter oil of almonds required one to fill out a DEA form, stating the use, expected amount used in a year, and a copy of the formula(e) one expects to use, along with name, address, business license number, and social security number. Too bad, because I noticed most if not all of their oils (legit or no) could be ordered in 5 gallon buckets, or larger, and their prices were VERY reasonable. This is a wholesale operation. They also carry olearesin of black pepper, also reasonably priced, and no DEA form required for that one, as of yet. I wanted to order some oleoresin of black pepper to try to isolate piperine, to try to potentiate my asthma medication, because I'm fucking tired of gasping for air, and extracting from peppercorns is a pain in the neck. But I digress. The moral is, if it's a list 1, don't even think of buying it, if you're into the shady side of the law, which assume most of you aren't. If you're crafty, you can find small amounts of what you're looking for, with no suspicion. good luck.

dr. nick - 8-10-2006 at 08:43

the Baking Almond flavour around here has also some plant oil in it, what would you say would be the best way to get it out there?

The method described by polverone sounds very good, but i fear the diethylether would also dissolve the oil ... or wouldn't it?

Maybe one should distill the benzaldehyde?
Or where is it more soluble in - in the nonpolar plant oil or in ethanol?
i'd like to avoid distilling if possible.

Thanks for any hint!

Thermal - 8-10-2006 at 23:28

I don't think you'd have decent results with anything other than distillation.

not_important - 8-10-2006 at 23:56

Quote:

Originally posted by dr. nick
the Baking Almond flavour around here has also some plant oil in it, what would you say would be the best way to get it out there?

The method described by polverone sounds very good, but i fear the diethylether would also dissolve the oil ... or wouldn't it?

Maybe one should distill the benzaldehyde?
Or where is it more soluble in - in the nonpolar plant oil or in ethanol?
i'd like to avoid distilling if possible.

Thanks for any hint!

It would take the plant oil, but that is left behind in the bisulfite addition product step.

At some point you are likely going to need to distill, depending on what is done to the benzaldyhed after isolation and what other compounds are in the source material.

Quote:

Originally posted by conducter
If swim didnt want to distill and didnt care about yields, would there be a way to evap the ether without overoxidizing the benzaldehyde? Maybe on very low heat and as soon as the ether is gone wash the benzaldehyde with water/sodium carbonate solution and then store in sealed container?

Better to extract while still in ether solution, evap in a distillation type setup to recover the ether and reduce the fire and other health risks. Flush the apparatus with CO2 or other oxygen free gas before heating, ditto for the bottle after filling.

Note that it's not going to take a high temperature to evaporate the ether, use a waterbath and hot plate or immersion heater. non-borosilicate glass can be used.

dr. nick - 9-10-2006 at 09:09

Hm, i see - so best will probably be to destill the whole almond flavor?. I guess i'd sacrifice a bottle and mix with Ethanol, just to see what happens but i think it won't help much ...

Seems the Almond flavor here does only contain plant oil and benzaldehyd, so how about oxydation when distilling that?

Thanks for the hints!

***edit:

oops, before i forget - when buying aethereous oil of bitter almond - how to get rid of the cyanide?

[Edited on 9-10-2006 by dr. nick]

pantone159 - 16-10-2006 at 16:33

I'm curious, what is the use for benzaldehyde that the DEA doesn't like?

I'm guessing to make Ph-CH2-CH(-NH-CH3)-CH3 but it isn't obvious to me how that would work.

Thermal - 17-10-2006 at 17:37

Methyl benzyl ketone primarily. But that's not something that's preferred to be discusssed here.

Edit: Yea I meant the nitropropene directly -> ketone

[Edited on 18-10-2006 by Thermal]

garage chemist - 17-10-2006 at 17:55

How is methyl benzyl ketone made from benzaldehyde? I'd think benzyl chloride ( -> benzyl cyanide -> phenylacetic acid) would be more useful for this.
Or do you mean by making phenyl-2-nitropropene and then converting this into the ketone?

In Europe, at least in Germany, benzaldehyde can be obtained from chemical suppliers without any problems (non-watched, non-controlled). It even is really cheap. Synthesis of Benzaldehyde is not a topic in german forums, as anyone can buy it.
Benzaldehyde is nice for simple and fun organic syntheses, like mandelic acid (requires NaCN though), benzoin (also requires NaCN), cinnamic aldehyde and cinnamic acid. Also beta-nitrostyrene (with nitromethane), this forms nice crystals from petroleum ether and has an interesting smell. Benzaldehyde is great for beginners in organic chemistry, as so many things can be made with it.

[Edited on 18-10-2006 by garage chemist]

evil_lurker - 17-10-2006 at 18:59

Quote:

Originally posted by garage chemist
In Europe, at least in Germany, benzaldehyde can be obtained from chemical suppliers without any problems (non-watched, non-controlled). It even is really cheap. Synthesis of Benzaldehyde is not a topic in german forums, as anyone can buy it.
[Edited on 18-10-2006 by garage chemist]

You do realize that you suck don't you?

They got all the good chems locked down over here in the USA.

chemoleo - 17-10-2006 at 19:25

I don't understand the problem anyway, benzyl alcohol can be easily obtained from photography suppliers, which can be neatly oxidised to lovely aldehyde with K2Cr2O7. Did it, and works wonderfully well!

Even if you don't have benzylalcohol, just oxidise toluene... there are threads on this. Ok this may not be a 'just do' effort...its a bit more difficult I suppose.

Polverone - 18-10-2006 at 00:11

Quote:

Originally posted by chemoleo
I don't understand the problem anyway, benzyl alcohol can be easily obtained from photography suppliers, which can be neatly oxidised to lovely aldehyde with K2Cr2O7. Did it, and works wonderfully well!

Did you isolate and determine the yield? K2Cr2O7 is inconveniently bulky considering its available oxygen, even if oxygen went 100% to producing aldehyde.

garage chemist - 18-10-2006 at 01:21

In another thread (sec. alcohol -> ketone) we recently talked about the FeBr3 catalyzed H2O2 oxidation of benzyl alcohols to benzaldehydes in over 80% yield. TCCA/KBr in DCM can also be employed for the oxidation of benzyl alcohol.
I also must say that benzyl alcohol is the best precursor to benzaldehyde you can get, much better than toluene.
I even think it would be worthwhile to make benzyl chloride from toluene, hydrolyze this to benzyl alcohol and oxidise it.
How is the availability of benzyl alcohol in the US?

Polverone - 18-10-2006 at 02:03

Quote:

Originally posted by garage chemist
In another thread (sec. alcohol -> ketone) we recently talked about the FeBr3 catalyzed H2O2 oxidation of benzyl alcohols to benzaldehydes in over 80% yield. TCCA/KBr in DCM can also be employed for the oxidation of benzyl alcohol.
I also must say that benzyl alcohol is the best precursor to benzaldehyde you can get, much better than toluene.
I even think it would be worthwhile to make benzyl chloride from toluene, hydrolyze this to benzyl alcohol and oxidise it.
How is the availability of benzyl alcohol in the US?

If you have benzyl chloride, can't you go directly to the aldehyde with the Sommelet reaction? I've never seen benzyl alcohol for sale in a brick and mortar store, but it is available online from numerous suppliers and is unregulated so far as I know. Best price I've seen recently is $40 for 1 US gallon (3.785 liters).

evil_lurker - 18-10-2006 at 09:06

The Sommelet does work, but keep in mind that benzyl chloride and benzaldehyde's boiling points are practically the same for all intents and purposes so if the reaction doesn't go to completion your gonna have contaminated product.

Maja - 18-10-2006 at 09:34

But you can easily purify benzaldehyde by bisulfite...

roamingnome - 11-11-2006 at 11:12

Prohibition my friends will soon be over.

You see in a free and ever growing educated society were commerce is king and the transport of resources and information never end, braking points are reached.

Today millions of dollars go into the commerce of beer and wine making. Many are employed to raise the grapes. The "controllers" realized that regulating sugar and water and harmless little ole yeast would be futile and immposible, hence prohibition was repealed.

The advanced collective mind of scientific thought is bringing forth such techniques and wonders that soon my friends no man shall controll.

in other words fuck the DEA

Baphomet - 22-11-2006 at 18:18

Roamingnome you have a point in that it will never be feasible to completely stop synthesis of illicit substances. But I don't think the governments are trying to eradicate it completely anyway. The true aim of their bans on various chemicals is to make synthesis as difficult as possible. For example it would take a lot longer to make meth using matchbooks and seaweed.

roamingnome - 19-1-2007 at 12:10

a few months wiser, i think prohibtion might be around for a bit....

the cheapo almond flavor that I found and grabed a bunch of to perform some small scale tests etc.....turns out to ultimintaly have been a complete distraction from more important issues....

I poured 8 or so bottles approx 500mls into distilation setup
applying vaccuum i suspect the alcohol was coming off at 20 degreees

the next fraction assumed to be water started coming over at 55-60 degrees

after shutting down the process the liquid left in the flask had ZERO smel
and appyling the patented "gil" taste test, it was more water!

the distillate also had zero smell...

my point is i can only assume the aromatic oil just evaporated off
i know thats its aromatic and volitle, but its boiling point is 179.1 here

I guess ill head to the getto and salt the water till a layer forms???

picketfence - 22-1-2007 at 08:21

Quote:

Originally posted by Organikum
Benzaldehyde is a list I chemical and watched. If you cannot get oil of bitter almonds locally OTC, I wouldnt recommend to order it from anywhere.

^That's right.

This can be made with toluene and ammonium persulfate in excellent yields, however it consumes a lot of ammonium persulfate.

Ammonium persulfate can be procured at electronics shops for some purpose which i dont give a shit about.

But again, myself I wouldn't want to be caught with a listed, or for that matter order a list chemical.

There's exceptions now though. See phosphorus and iodine are both listed items, however psuedoephedrine is no longer available as in oz atleast it's been replaced by phenylephrine, so they could never even get you for conspiracy - that's just my opinion though.

[Edited on 22-1-2007 by picketfence]

[Edited on 22-1-2007 by picketfence]

Coldfinger - 23-1-2007 at 09:42

Quote:

This can be made with toluene and ammonium persulfate in excellent yields, however it consumes a lot of ammonium persulfate.

the ammonium persulfate is used as an etching compound for production of PCBs for electronics, it by itself is no challenge to find.

However, the oxidation itself looks better on paper than it is in practice, often the toluene will not be fully oxidised and will only result in benzyl alcohol, or it will be oxidised too much and you are left with benzoic acid. It is also an exothermic reaction and heating it too rapidly or from experience, to over 70deg C. it tends to get into a 'runaway' situation, where it will boil rapidly, with alot of the liquid shooting out of the condensor or ending up all over your workspace.

I am not saying it is impossible, it is just a bit more sensitive than it appears.

Quote:

There's exceptions now though. See phosphorus and iodine are both listed items, however psuedoephedrine is no longer available as in oz atleast it's been replaced by phenylephrine, so they could never even get you for conspiracy - that's just my opinion though.

i disagree, just because something is no longer available OTC does not mean that you can not be charged with conspiracy to manufacture. Pseudoephedrine is still highly illegal to possess, in my part of the world anyway. Someone would have to be out of their mind to even consider messing with it.

roamingnome - 23-1-2007 at 10:07

i think one needs to step up to zeolites if you really want a good way to convert toulene to benzaldehyde

Zeolite Y
http://www.personal.utulsa.edu/~geoffrey-price/zeolite/fau.h...

...shoot can find the other refs at this time....

http://www.springerlink.com/content/n16548546t166jx5/

bio2 - 23-1-2007 at 11:20

So after all these years of discussing PhCHO
from bitter almond extract or diluted flavoring
has anyone published a procedure that's workable?

This doesn't seem so difficult after all.

Sauron - 23-1-2007 at 23:05

Anyone can say "fuck the DEA" as talk is cheap.

However if the DEA says "Fuck you!_ you might find it costly.

Or in other words, to paraphrase John F.Kennedy,

"Ask not what your country can do for you. Ask what your country can do TO you."

I used to say "Fuck the ATF". And in 1975 I had a run-in with an ATF undercover agent who tried to clumcily entrap me. I made a fool of him. For the next ten years he waited to get even. One day he got his chance and he took it. It was such an egregious case Jack Anderson wrote a column about it.

Anyway, my advice is, don't go out of your way to piss off powerful agencies.

Life will supply you with enough problems without all that.

PS to above:

Unless the USC has seriously changed, a criminal conspiracy requires at least two conspiraors. There's no such thing as a conspiracy of one. An individual cannot conspire with himself.

Furthermore with exception of some tax codes and some firearms codes that are really tax codesa, all criminal laws place the burden of proof of criminal intent on the prosecution. If you are not using benzaldehyde to prepare drugs or precursors for drugs that are scheduled, then where's the criminal intent? (n legal jargon, the phrase of art is "mens rae".

Naturally if you are a drug user, drug dealer, have a drug record, associate with druggies, etc. then the prosecution will have an easy time with this burden.

[Edited on 24-1-2007 by Sauron]

picketfence - 24-1-2007 at 07:13

Quote:

Originally posted by Coldfinger

Quote:

However, the oxidation itself looks better on paper than it is in practice, often the toluene will not be fully oxidised and will only result in benzyl alcohol, or it will be oxidised too much and you are left with benzoic acid. It is also an exothermic reaction and heating it too rapidly or from experience, to over 70deg C. it tends to get into a 'runaway' situation, where it will boil rapidly, with alot of the liquid shooting out of the condensor or ending up all over your workspace.

I am not saying it is impossible, it is just a bit more sensitive than it appears.

No you see I've actually done the rxn and fractionally distilled - from memory the purity was >90% as was the yield.
The patent isn't posted here.

Quote:

Who would keep ephedrine though except a desparate, dumb meth cook who has no other options?

The only option is a plantation of ephedra sinensis or other high yielding (like 1% at best) and a small garden with a few plants is just laughable.

And they can forget the overhyped biosynthesis with benzaldehyde and acetaldehyde, that was never an at-home, in-a-bucket job as many wanted to believe it was, it requires highly controlled conditions to reach L-PAC.

Anyway, I partially agree with you, as being caught with anby listed chemical including RP would not be nice. However there's better alternatives to phosphorus that're non suspicious, and iodines used in photography.

[Edited on 24-1-2007 by picketfence]

Hilski - 24-1-2007 at 07:18

Quote:

And they can forget the overhyped biosynthesis with benzaldehyde and acetaldehyde, that was never an at-home, in-a-bucket job as many wanted to believe it was, it requires highly controlled conditions to reach L-PAC

{EDIT} Never mind. It's not even worth arguing about.

[Edited on 24-1-2007 by Hilski]

picketfence - 24-1-2007 at 07:25

Exactly - that's the past.

Bisulfite Addition Weirdness

einstein(not) - 14-5-2009 at 16:27

I just tried bisulfite addition to imitation almond extract with weird results. The extract I'm using contains the following ingrediants: Water,Alcohol(36%) and Benzaldehyde.

The following volumes were used in all experiments.

50ml extact
50 ml ether,hexane(starting fluid)
50ml saturated sulfite solution

Experiment 1
The extract was dryed with oven roasted rock salt for 2 hours decanted and ether was added. The mixture was shaken vigorously in a sepratory funnel and the lower phase drained off. The lower phase still had a strong smell of benzaldahyde. The upper layer was dumped into bisulfite solution and stirred for 5 minutes. No precipitate was detected. The same was repeated with the lower layer with the same results.

Experimient 2
Same as above except the extract was dried with molecular seives. Same result.

Experiment 3
Same as above except the extract was dried with calcium chloride(damp-rid). This time when the lower layer was dumped into bisulfite solution a white suspension resulted. When this suspension was then added to the lower layers of the previous experiments they became white suspension as well.

I can tell that some of this suspension is bisulfite adduct but I'm not sure it all is.

So my question is does calcium chloride react with bisulfite,alcohol or benzaldehyde is some way that caused this? Or is there an additive in the extract to prevent separation? Is the procedure flawed? This is my first attempt at bisulfite addition.

[Edited on 15-5-2009 by einstein(not)]

[Edited on 15-5-2009 by einstein(not)]

DJF90 - 14-5-2009 at 17:18

Bisulfite addition usually requires adding the aldehyde to a solution of sodium bisulfite and then cooling, can take an hour or so to form; at least it did in the procedure I read IIRC.

[Edited on 15-5-2009 by DJF90]

bquirky - 14-5-2009 at 18:10

I dont relly know anything about organic chem so im likely way off

but if your looking for large amounts of almond extract why not just buy a bunch of almonds and extract the oils yourself ?

at least then you would know that it contains what almonds are supposed to contain

einstein(not) - 14-5-2009 at 22:55

Where can I find detailed information on the proper precedure? One suitable for a beginner. Preferably with explainations why each step is done in a particular way.

Nicodem - 14-5-2009 at 23:51

There are plenty of examples in the literature, just pick one and try it out.
CaCl2 form chelates with alcohols just like with water.
Bisulfite adducts of aldehydes are generally water soluble, some better some worse. So if your goal was to get a precipitate of the adduct, what was the point in having a biphasic mixture? Though it is true that aldehydes can be extracted in to the aqueous NaHSO3 solution in the form of the bisulfite adduct (RCH(OH)SO3Na), you do not seem interested in extracting the adduct, but rather precipitating it (that is if I understood correctly, as it would be nice if you would bother describing what you do and what you want more properly).

Sedit - 15-5-2009 at 09:04

I recently figured I would attempt to extract the BzO from the tinctures found in the super market and the results I obtained where unimpressive to say the lest. There was so little BzO in them is wasn't even funny. Just a few very fine droplets of oil from 3 bottles that I didn't even waste my time attempting to extract it. I know that not all extracts are made equally but for anyone that wants to attempt this dont spluge and by 20 bottles until you are sure there is a decent amount in there to make it worth extracting in the first place.

Arrhenius - 15-5-2009 at 09:14

There are synthetic bitter almond oils available that are >90% benzaldehyde. I found it very easily purified by fractional vacuum distillation.

einstein(not) - 15-5-2009 at 09:28

Well I'm trying to separate the benzaldehyde from the extract. I tried vacuum distillation once and ended up with red cinnimon smelling oil. Learning for me has always been a hands on process and what I was hoping to learn with these experiments is how to properly extract a disolved aldehyde from a solution. Imitation almond extract was available so that's what I used. As was the starting fluid. I eventually I would like to move on to actual aldehyde synthesis but without knowing how to extract the finished product what would be the point.

One thing I've learned is that I don't understand how to extract properly from alcohol solutions.

I considered basic A/B extraction but after my failure with vac. distillation I opted for what sounds like a milder method.

Arrhenius - 15-5-2009 at 09:58

Really, vacuum distillation is a slam dunk if your starting oil has a good amount of benzaldehyde in it, and if your vacuum distillation setup is legit. I'll post a writeup if you guys don't believe me.

Acid-base extraction will not work with benzaldehyde, as it doesn't contain an acidic or basic moiety. Can you explain more thoroughly the procedure you used? Where does the starting fluid come into the distillation?

Benzaldehyde is quite fragrant, and any almond essence or almond extract product used for cooking is likely not to have very much in it. Products specifically for fragrance applications are likely to be quite concentrated. It really depends if you want the benzaldehyde, or you want the challenge of trying to squeeze a little bit out of an OTC product. If you're starting with an alcohol solution, you can pump off the alcohol with a vacuum pump at room temp.

One thing to note with distillations is that if you have water present, you will actually be conducting a steam distillation, and you won't fractionate your mixture.

[Edited on 15-5-2009 by Arrhenius]

[Edited on 15-5-2009 by Arrhenius]

einstein(not) - 15-5-2009 at 10:52

Starting fluid wasn't used in the distillation. Only the bisulfite procedure.

Vacuum distillation experiment

236ml of imitation almond extract (water, alcohol(36%) and benzaldehyde) was placed in a 500ml RBF 24/40 single neck to which was connected a thermometer adapter with a sloped side side connector. A 300mm jacketed allihn condenser was attached on the receiver end to a 45 degree vacuum adapter attached to a 500 erlenmeyer flask.
The flask was place in the mantle and slowly heated over approx. 3 hours to 110C while vacuum was applied. The reading on the gauge showed 15 which I assume is inches Hg. Condenser coolant was maintained at 0C. Distillate came over at approx. 2 drops per second. Almond smell filled the work area I assume from the vacuum pump. When boiling slowed almost to a stop the mantle, vac. pump, and coolant pump was turned off. The residue was approx. 15ml of a dark red oil smelling of cinnimon. Washing with 20ml of Dh2o made no difference in color.

Wonder if imposing a wash bottle with bisulfite solution between the vacuum pump and the receiver might catch any losses?

If there is alcohol present along with the water is it still a steam distiiation?

[Edited on 15-5-2009 by einstein(not)]

Arrhenius - 15-5-2009 at 11:04

So what color was the distillate? In a vacuum distillation the benzaldehyde should come over as a clear fraction. If you have a vacuum gauge on the setup, try using a nomograph to correct the BP and see if you're close to that of benzaldehyde. At this point the pot residue should be unwanted contaminants.

If you want to start with that almond extract, I think you should try to get the benzaldehyde away from the water first. Dilute the extract with water, extract with ether or ethyl acetate, dry with magnesium sulfate if possible, and strip off the solvent. This will prevent water from messing up your distillation.

Your loss in the vacuum pump should be really negligible. The boiling point of benzaldehyde is a bit too high for your pump to be stripping it off of the distillate side of the apparatus, but your nose is really sensitive to it. Don't worry about losses there.

Also: 3 hours sounds like a long time for a distillation. It's okay to get it going a little faster. Generally, applying heat will promote side reactions, so it's favorable to get your product out as quickly as possible.

[Edited on 15-5-2009 by Arrhenius]

einstein(not) - 15-5-2009 at 11:17

The distillate was crystal clear and smelled of ethanol with no layering.

I bet you're right about going too long. I thought the residue would be where I would find the benzaldehyde so I went slow to keep from pushing it over. Think I might try it again with what I have left.

Nicodem - 15-5-2009 at 12:05

What is the declared concentration of benzaldehyde in that "imitation almond extract"? If it is a solution of benzaldehyde in 36% alcohol then it can not contain more than a few percent, maybe 10% utmost, of benzaldehyde.
Also, you can not separate benzaldehyde from such a solution with fractionation, because once the cosolvent gets removed in the form of 96% ethanol you end up with a biphasic system from which benzaldehyde starts distilling with steam. You must first extract the benzaldehyde and then distil it (if there is anything more than a couple of % in there!).
Have you checked the pH of your "imitation almond extract"? If it is older than a couple of months and if it was not protected from air it is probably mostly oxidized to benzoic acid.

Sedit: It would be nice if you could avoid using "BzO" as a shorthand for benzaldehyde. Using shorthand formula is useful but in needs to be done properly. Bz- is stands for the benzoyl group (PhCO-) and if you want to use it for benzaldehyde you must write BzH. BzO stands for the benzoyloxy radical (PhCOO*).

Sedit - 15-5-2009 at 12:12

I did not know that thank you Nicodem. So when people use BzCl for short hand for benzyl chloride they are really writing PhCOCl?

The extract I was talking about was water, 36% alcohol mixture. Mine contained almost no benzaldahyde.

Nicodem - 15-5-2009 at 12:34

Quote: Originally posted by Sedit

I did not know that thank you Nicodem. So when people use BzCl for short hand for benzyl chloride they are really writing PhCOCl?

Yes, BzCl would stand for benzoyl chloride. Benzyl chloride would be BnCl. But "Bz" is nowadays avoided in scientific literature because historically its use is not consistent (some authors used it for benzyl as well and this inconsistency can even be found in some of the old Chem. Abstr. entries). Personally I'm also against its use since it brings nothing but confusion and since using PhCO instead is just as simple. With benzyl (Bn) luckily there is no historical inconsistency.

Sedit - 15-5-2009 at 12:44

Ok I understand now. I use to write BnCl until someone corrected me and said that BzCl is the way it needs to be written and I blindly followed after that. Sorry for any confusion.

einstein(not) - 15-5-2009 at 15:01

Doesn't show percentage and I haven't been able to find anything online. It is a well known brand that makes many different flavorings. M******k Only reason I chose to try it was I noticed an 8 ounce bottle of it at our local foodservice retail outlet while my wife shopped for wedding food.

The procedure I tried was based on Polverones post on the first page of this thread.

Quote: Originally posted by Polverone

I wanted a small amount of benzaldehyde to try making bisulfite adduct with. So I grabbed from the kitchen a bottle containing "water, 36% alcohol, and benzaldehyde" (the usual artificial flavoring stuff) and saturated some of the liquid with table salt in a large test tube. Then I extracted by shaking it several times with unrefined automotive starting fluid and pipetting off the top layer. This top layer gave a thick mass of white, flocculent adduct when shaken with an alcoholic bisulfite solution made according to Vogel and left to stand for several minutes. Yield of adduct was not determined by weighing because I did not want to dry it. Half the portion of adduct was filtered then while still wet shaken with sodium carbonate solution in a smaller test tube to give a visibly distinct and heavenly-smelling layer of benzaldehyde on top of the aqueous solution. If you're not interested in the behavior of bisulfite adducts, the starting fluid can simply be evaporated away to give fairly pure benzaldehyde, though if done in open air you may well lose much of the aldehyde to oxidation.

This would be a very expensive way to get benzaldehyde if you rely on the usual supermarket flavorings, but I've seen inexpensive containers of up to 300 ml artificial almond flavor at stores that target restaurant-scale customers. And of course the small Lorann Oils containers of pure benzaldehyde ("almond oil") are also available OTC at specialty cake/candy places. If you need more than 100 grams or so, though, I think the cassia oil method looks much more attractive.

[Edited on 15-5-2009 by einstein(not)]

Arrhenius - 16-5-2009 at 10:27

Why not have another shot at the vacuum distillation? I have a pretty good vacuum pump, which helps a lot. You'll really have to heat the boiling flask quite hot to get the benzaldehyde to come over; probably >100ºC.

Nicodem's comment about water reiterates what I said about extracting the almond extract with ether/ethy acetate first. However, I think you might find it considerably easier to just dry the extract with anhydrous magnesium sulfate (epsom salt... heat it in the oven for a bit to make it anhydrous). Add the magnesium sulfate, let it sit for a while, then filter it off and carry the filtrate onto the distillation.

Nicodem - 16-5-2009 at 10:37

Or you could repeat the extraction like Polverone did with forming the bisulfite adduct in the usual fashion instead of those improvisations you tried.

Alastair - 14-10-2011 at 23:30

Can purification be done with simple Na2SO3 (sodium sulfite)?

Alastair - 14-10-2011 at 23:31

Whoopsies, just realised this was an 2+ year old thread, ima post the question elsewhere.

cal - 15-9-2012 at 21:15

Quote: Originally posted by Mendeleev

You know what, fuck the DEA, benzaldehyde is restricted, but they can't regulate an essential oil in my opinion. At least I don't think bitter almond oil would actually be considered a LIST 1 chemical since it isn't pure benzaldehyde. So even if it is watched, they can't do anything about it legally. If they get on you about it you can tell them to piss off since it isn't a chem supplier but an aromatherapy store.

[Edited on 30-12-2004 by Mendeleev]

I have bought oil of bitter almond from a food flavoring supplier for years now. It is just a little more expensive.

Doc B - 21-9-2012 at 03:54

The flavouring round these parts has glycerine and propylene glycol along with water and natural almond flavouring. Any suggestion on extraction, given the similarities of bp and solubilities of the ingredients?

Bitter Almond Extract

cal - 21-9-2012 at 05:04

Quote: Originally posted by Organikum

Benzaldehyde is a list I chemical and watched. If you cannot get oil of bitter almonds locally OTC, I wouldnt recommend to order it from anywhere.

The purification depends on
- the oil, often alcohol and other stuff is added
- what you need it for, different reactions demand different grades of purity, or tolerate certain impurities or not.

I have been purchasing Oil of Bitter Almond Extract from food supply companies for years now with no problem as it is not regulated as a food additive. You can walk in to any restaurant supply and buy it cash no records all over the USA. :cool:

barley81 - 15-1-2013 at 05:14

I found a Polish supplier of benzaldehyde on eBay. $23 for 250mL, shipped to USA. It's a good deal, but customs would have a problem with this, right?

DH2 - 25-5-2013 at 10:05

You can easily get bitter almond oil. There's a local store to me that sells it. Also, there's a brand out there that sells a diluted bitter almond oil that's 48% vegetable oil, 52% bitter almond oil. Seeing the astronomical difference between boiling points, it's a a matter of simple distillation to just separate the two.

Bottom line is that benzaldehyde is not exactly hard to come by. Even if you can't locate bitter almond oil (the nicest smelling essential oil of all time, in my opinion) you should be able to easily make it from easily acquirable things like benzyl alcohol, DMSO, etc.

Furboffle - 4-6-2013 at 15:10

I quit working at a restaurant Cigar City Brewpub a couple months ago, it amazed me how much chemistry was involved in the cooking, they would buy pure chemicals for a lot of the recipes mainly desserts and their staple, beer. But we had gallon jugs of oil of almond in the pantry, I check the concentration and was shocked it was pure benzaldehyde. They got that specifically from the Sysco restaurant supply store. Luckily my relatives have a sandwich shop so I have a ticket in. But if y'all have Sysco stores in your towns and know someone who runs or owns a restaurant just go buy a jug no questions asked.