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CrimpJiggler
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Synthesizing this random compound
I'm getting sick of learning all this theory and not putting it into practice so I've decided to use some of the things I've learned recently to
synthesize a random compound. I'm going to hydrolyze aspirin to salicylic acid. Then I'm going to do a Kolbe electrolysis on the salicylic acid to
form 2,2-biphenol. Then I'm going to do a Williamson ether synthesis using dichloromethane to form this:
![](http://img838.imageshack.us/img838/4237/18971053.png)
I can't find any information on that compound at all though. I think they're called benzodioxepines but I can't find any info on their properties. I
like the idea of synthesising a random compound like this. I might just go mad and synthesize some bizarre, complex molecule that has never been
synthesized before. Do any of you here have much experience with synthesizing random compound which, to your knowledge, have never been knowingly
synthesized before? I'm thinking along the lines of extracting some large molecules from plants and fusing them together to produce god knows what. It
would be very easy to make compounds that the world has never seen before. For example I doubt anybody has tried reacting a salamander steroid:
![](https://upload.wikimedia.org/wikipedia/commons/thumb/3/3f/Samandarin.svg/200px-Samandarin.svg.png)
with mosquito pheremones:
![](http://blogs.princeton.edu/chm333/f2005/group3/pictures/app_agro1.gif)
before.
[Edited on 11-1-2012 by CrimpJiggler]
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Bot0nist
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What level of organic chemistry education and/or training do you have, if you don't mind me asking.
It would be fun to synthesize a previously undiscovered compound in an armature setting. Strenuous effort would have to be made to analyze the end
product to be certain of its stability, purity, and whether or not it is in fact a stable molecule (with a use? Is that a condition?) and is
previously undiscovered.
[Edited on 11-1-2012 by Bot0nist]
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bahamuth
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First molecule is called dibenzo[d,f][1,3]dioxepine.
And I have to agree that it would be fun, but would keep far away from biological active stuff like hormones.
They tend to do "stuff" in all species of eukaryotes, we wouldn't want to accidentally end up with say, an abnormly elongated male reproductive organ
now would we..
Any sufficiently advanced technology is indistinguishable from magic.
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I think williamson ether synthesis would give a lot of ring alkylated product (and side products arising from there). In a mechanism different
from...but still similar to the Reimer–Tiemann formylation.
Off the top of my head, I can't think of a great way of making this...best to check the lit.
"Titanium tetrachloride…You sly temptress." --Walter Bishop
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bahamuth
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The litterature suggest starting from 2,2-biphenol, using 2,2-dimethoxypropane in chloroform with tosic acid as catalyst, reflux for 72 hours to get
89% yield.(1)
Without me knowing all that about the limitations or this method couldn't one substitute 2,2-dimethoxypropane with dimethoxymethane to get
dibenzo[d,f][1,3]dioxepine?
Understanding that I am derailing especially since this compound is known but got intrigued.
Ref.
1. https://dspace.ucalgary.ca/bitstream/1880/42698/1/38497Passa...
Any sufficiently advanced technology is indistinguishable from magic.
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CrimpJiggler
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Quote: Originally posted by Bot0nist ![](images/xpblue/lastpost.gif) | What level of organic chemistry education and/or training do you have, if you don't mind me asking.
It would be fun to synthesize a previously undiscovered compound in an armature setting. Strenuous effort would have to be made to analyze the end
product to be certain of its stability, purity, and whether or not it is in fact a stable molecule (with a use? Is that a condition?) and is
previously undiscovered.
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Very little. The only real organic chem experience I have is from the labs at college and considering I've only done 2 semesters of organic labs in
total, that doesn't amount to much. You're right, I'm dreaming here. Even attempting to make that dioxepine (or whatever it is) having no experience
with these particular reactions in my poorly equipped, home lab is silly. I didn't really need a reality check, I would have came to this conclusion
anyway, I was just brainstorming because I'm a practical learner and need to constantly apply my knowledge in practical matters, even if only in my
head. As for analysis of the final product, I can't even afford a melting point apparatus so I wouldn't be able to find out very much about the
product. Yeah I would love to get involved in synthesising new compounds. My long term plan is to become a research chemist. Working for a company, I
will have access to a well equipped lab but its the company deciding what you research. When I become a trusted employee, I bet I'll be able to talk
them into letting me conduct my own research on the side but I'm not even out of college yet so it will be a long time before I get there.
Quote: Originally posted by bahamuth ![](images/xpblue/lastpost.gif) | First molecule is called dibenzo[d,f][1,3]dioxepine.
And I have to agree that it would be fun, but would keep far away from biological active stuff like hormones.
They tend to do "stuff" in all species of eukaryotes, we wouldn't want to accidentally end up with say, an abnormly elongated male reproductive organ
now would we..
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True, one has to be mighty careful dealing with biologically active compounds. Non biologically active compounds often do stuff too, i.e.
dichloromethane is a suspected carcinogen, 4,4-biphenol (I don't know about 2,2) has estrogenic (overexposure may give me a pair of breasts to
accompany my abnormally elongated male reproductive organ lol) and cytotoxic properties but the major difference I suppose is I would have to ingest
those two compounds in relatively large quantities to produce profound physiological changes.
Quote: Originally posted by smuv ![](images/xpblue/lastpost.gif) | I think williamson ether synthesis would give a lot of ring alkylated product (and side products arising from there). In a mechanism different
from...but still similar to the Reimer–Tiemann formylation.
Off the top of my head, I can't think of a great way of making this...best to check the lit. |
I suspected the synthesis wouldn't work out as intended. For a beginner such as myself, they rarely do. Are you sure this reaction would yield many
ring alkylated products though? I read about a dichloromethane methylenation of a 1,2 pair of aromatic hydroxyl groups before so I assumed that it
would work for a pair of hydroxy groups on different rings but there are many things I'm probably not considering.
[Edited on 11-1-2012 by CrimpJiggler]
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Bot0nist
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Sounds like a great goal CrimpJiggler. Oh, I wasn't trying to discourage you or give you a "reality check." I was merely curious in light of you
wanting to conduct some higher level syntheses. Good luck in college and career.
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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Dr.Bob
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If you are still in college, most chemistry professors would love to have a student interested in independent study work, and will possibly set you up
in a lab with the chemicals and equipment. Not all will do this, but I was able to do that (a few years back) and I ended up working in the lab for
2 years as an undergrad before going to gradual school. I made all sorts of stuff and was able to work with a few grad. students as well as
postdocs. It was a great time, and I was in geek heaven. That way you get to do some chemistry, but with the right starting materials, good
equipment, a safe work space, and some good advice, hopefully.
That is not to say that home science is not fun, but if you are at a college, then it is really worth it to do some research there.
As a note, it is difficult to get DCM to react with anything, as the two chloros tend to block the molecule from SN2 type reactions except under harsh
conditions. But there may be ways to do that. But there are ways to make those compounds. Formaldehyde is the more likely way, but much more
hazardous.
Bob
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GreenD
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I too volunteered in a research lab on campus. You learn a lot (no matter what the chemistry is) especially technique / apparatus etc.
I wasn't making anything that interested me, but I became familiar with solvents, column chromatography, re-crystallizations, nmr, IR, TLC, vacuum
distillations, etc...
We made polymers. I HATE polymers. I think they are the most boring subject in chemistry. But when I finally landed a "real" job - boy do I miss the
academic atmosphere. Working for a big company blows ... althought. if it is SO
big, sometimes you can "get" things
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GreenD
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Quote: Originally posted by Dr.Bob ![](images/xpblue/lastpost.gif) | As a note, it is difficult to get DCM to react with anything, as the two chloros tend to block the molecule from SN2 type reactions except under harsh
conditions.
Bob |
I may be way out of line but doesn't DCM undergo a equilibrium with Iodide or bromide to form mono/dihalo methane - then an SN1 would be easier. I
vaguely remember reading this when people were trying to get a di-methoxy bridge compound. The purity of the end product would be dirty, but just
sayin.
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Dr.Bob
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Diiodomethane will react in some cases to form methylenedioxy compounds or other cyclic systems, but these are not easy reactions. I can't say that
I know how they make Diiodomethane, but it might well be possible to make via some exchange reaction, but it does not seem easy, since I have run
brominations in DCM with no sign of any reaction of the solvent, nor do I remember that as a prep for it, but my mind is aging fast.
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fledarmus
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If you are really interested in making compounds that have never been made before, find a research group at your University working in medicinal
chemistry. The traditional flow of medicinal chemistry is to find a known compound which shows some activity, buy up a bunch of similar compounds and
test them for activity in the same assay, then use the structural information that you've gotten to design new molecules which aren't commercially
available and many times have never been synthesized before, for synthesis and testing.
Making truly random molecules gets boring quickly - it's much more of a challenge to design a previously unknown molecule that you think will have a
specific function, figure out how to synthesize, put a few mgs of material in a bottle, and have it tested to find out if you were right.
This is my full-time job. I make at least a hundred previously unpublished molecules every year, many of which turn out to be useless and never get
published even by me. But it's a great feeling when the compounds do get published and you get to add a few extra CAS numbers to the databases!
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Panache
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Quote: Originally posted by GreenD ![](images/xpblue/lastpost.gif) | I too volunteered in a research lab on campus. You learn a lot (no matter what the chemistry is) especially technique / apparatus etc.
I wasn't making anything that interested me, but I became familiar with solvents, column chromatography, re-crystallizations, nmr, IR, TLC, vacuum
distillations, etc...
We made polymers. I HATE polymers. I think they are the most boring subject in chemistry. But when I finally landed a "real" job - boy do I miss the
academic atmosphere. Working for a big company blows ... althought. if it is SO
big, sometimes you can "get" things |
Omg i am your doppelganger (fuck knows how to spell that), god i can still remember the summer jobs for professors, sitting in their office on the
first morning of 'work', they outlined the problem they were working on, how involved it was how broad, how pertinent, then you were taken to a small
windowless instrument room in the bowels somewhere and told to take 4000 glancing angle ftir spectra on some polymer film, which were all virtually
indistinguishable. Two and a half months later you were done.
Followed up the nxt summer resplitting twelve years worth of soil samples for reanalysis with a new technique. Ever used a sample splitter, its highly
skilled.......next caveman Unga pours the soil into the splitter again and again and again and again
Then finally an awesome summer job, hoechst, small surfactants plant, r&D team of three simply trying to make this surfactant or that additive so
we could steal the business off another company, different organic reaction every day, subsidied canteen, first day of work, second of january, meet
the two coworkers, morning tea, ask how was your new years, lady says "i threw a party, guess it was a mistake, people were doing other things, not
one person came...." really long awkward pause, starts crying, other worker who knew her pants her on the shoulder, takes two weeks off, god awful few
minutes.
Back on topic, novel compounds??. Wtf??? Whats wrong with mixing ephridrine,iodine and whatever popping a balloon over it and rah rah, again and again
and again and again ........
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GreenD
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cause then breaking bad happens.
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AndersHoveland
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Just react 2,2'-hydroxybiphenyl with formaldehyde, then distill.
[Edited on 13-1-2012 by AndersHoveland]
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GreenD
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maybe a bit off subject, but a bi-phenyl molecule would be planar? or would the two phenyl's have some angle of rotation about the phenyl-phenyl bond?
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CrimpJiggler
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Quote: Originally posted by Dr.Bob ![](images/xpblue/lastpost.gif) | If you are still in college, most chemistry professors would love to have a student interested in independent study work, and will possibly set you up
in a lab with the chemicals and equipment. Not all will do this, but I was able to do that (a few years back) and I ended up working in the lab for
2 years as an undergrad before going to gradual school. I made all sorts of stuff and was able to work with a few grad. students as well as
postdocs. It was a great time, and I was in geek heaven. That way you get to do some chemistry, but with the right starting materials, good
equipment, a safe work space, and some good advice, hopefully. |
I didn't think of that. That would be brilliant. I don't talk much to the lecturers but the people that run the labs know me and know that I take
chemistry seriously. I've talked to a few of them about cutting edge chemistry topics and most of them seem to be as interested as I am. I'm going to
come up with a way to approach them and see if I can do this. Thanks for the idea.
Quote: Originally posted by GreenD ![](images/xpblue/lastpost.gif) | I too volunteered in a research lab on campus. You learn a lot (no matter what the chemistry is) especially technique / apparatus etc.
I wasn't making anything that interested me, but I became familiar with solvents, column chromatography, re-crystallizations, nmr, IR, TLC, vacuum
distillations, etc...
We made polymers. I HATE polymers. I think they are the most boring subject in chemistry. But when I finally landed a "real" job - boy do I miss the
academic atmosphere. Working for a big company blows ... althought. if it is SO
big, sometimes you can "get" things |
I'm gonna do that. I'd be happy taking part in any kind of chemistry research. I used to find polymers boring but my perspective took a 180 degree
turn when I started considering the potential diversity of polymers. There are so many things that can be polyerised and there are so many variables
to exploit (i.e. copolymers, branching, modifying pendant groups etc.), the field of polymer chemistry is really in its infancy. The same could be
said about chemistry in general, thats what I love about it.
Quote: Originally posted by fledarmus ![](images/xpblue/lastpost.gif) | If you are really interested in making compounds that have never been made before, find a research group at your University working in medicinal
chemistry. The traditional flow of medicinal chemistry is to find a known compound which shows some activity, buy up a bunch of similar compounds and
test them for activity in the same assay, then use the structural information that you've gotten to design new molecules which aren't commercially
available and many times have never been synthesized before, for synthesis and testing. |
Med chem is my favourite subject and is the one I would like to research most. I have plenty of ideas for lead compounds. For example, ibogaine is
being used all over the world to cure heroin (and other drug) addiction. I suspect that the ibogaine molecule can be modified so that it no longer has
the hallucinogenic properties but retains its withdrawal curing properties. Drugs like LSD and psilocybin had been known for years to cure cluster
headaches and by attaching a bromine atom to LSD, they discovered an analogue which is not hallucinogenic but still cures the migraines. I could go on
all day about lead compounds that I would research if I was allowed do my own research in a well equipped lab. Med chem is the reason I got into
chemistry in the first place. I'm gonna see if there is a med chem research group at my college because I would love to be a part of a group like that
and I believe I would have a lot to offer since I was planning on becoming an ethnobotanist before I chose chemistry. I envy you. I hope someday to
get a job like yours. I would be in heaven. Getting paid to do what I would do for free.
[Edited on 13-1-2012 by CrimpJiggler]
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CrimpJiggler
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Quote: Originally posted by GreenD ![](images/xpblue/lastpost.gif) | maybe a bit off subject, but a bi-phenyl molecule would be planar? or would the two phenyl's have some angle of rotation about the phenyl-phenyl bond?
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I assume they'd be free to rotate. Forming the new methylene bridge would lock the molecule into a single conformation, probably a planar one since
that would spread the atoms furthest away from each other.
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turd
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Quote: Originally posted by CrimpJiggler ![](images/xpblue/lastpost.gif) | I suspect that the ibogaine molecule can be modified so that it no longer has the hallucinogenic properties but retains its withdrawal curing
properties. |
Yes, because we must under all circumstances prevent that people think about their life from another perspective! Has it occurred to you that maybe
the psychedelic properties are the basis of the ostensible addiction "curing" properties? Physical withdrawal is not the hard part in treating
addiction - the mechanisms are well understood and the medication for that exists.
And sorry I don't believe in wonder cures, sounds a little bit like a scam akin to psychoanalysis or hypnosis. And the success stories have that
cognitive dissonance feeling to them of people who paid a lot of money for a not really pleasurable psychedelic experience. Jaded? Maybe.
All in all I suggest you collect a few more years of experience with humans before you go into drug design. I fear addiction is not as simple as
synthesizing an antagonist for the "addictive behaviour receptor".
Edit: Ultra-embarrassing typo.
[Edited on 14-1-2012 by turd]
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Panache
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Addiction for most of time is pretty weell the most useless undescriptive word around. Its more mired in self-righteous, holier than thou religious
connotations. Please use the word dependance, it's much nicer.
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turd
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Sorry - as a non-native I was not aware of these connotations (and neither is my dictionary). I will of course use the less loaded word in the future.
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watson.fawkes
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Quote: Originally posted by Panache ![](images/xpblue/lastpost.gif) | Addiction for most of time is pretty weell the most useless undescriptive word around. Its more mired in self-righteous, holier than thou religious
connotations. Please use the word dependance, it's much nicer. | At risk of inciting a complete derailing, I
want to point out there's an emerging school of research that identifies addiction and dependence as separate processes, frequently co-morbid. In this
school of thought, addiction is a principally psychological process and dependence is a principally physiological one. It seems that there may be
psychological co-factors already present when addiction occurs, and that chemical dependence on a drug may be insufficient as a singly-causal factor.
When operating by itself, a drug commonly called 'addictive' does not always or necessarily cause addiction.
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GreenD
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As far as I know it is the hallucinogenic and psychadelic properties of ibogaine that allow users over come their addicition - that is atleast how
ayahuasca works.
Modifying a psychedelic to get rid of the psychedelic properties is like buying a car and ripping the wheels off and driving around in it.
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fledarmus
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Heroin was first synthesized when somebody thought that acetylating morphine might make it less addictive. Didn't quite work that way...
There's been a lot of discussion over the last five decades over just what constitutes addiction, what constitutes dependence, and whether either is a
physical or strictly psychological issue. There are drugs which will change the way the body produces certain substances, and when the drugs are
removed, the body may take a while to restabilize, or will never really restabilize. These drugs cause chemical dependence, and the body's physical
reaction to the lack of the drug is called withdrawal. IF you've ever had to take the steroid prednisone, you know what I mean - this drug is given in
a fairly large dose to counteract allergic reactions, but then must be tapered off slowly to zero because the body quits producing one of its own
steroids in response.
Then there is a psychological condition bordering on obsession where people simply need to do something or take something, even though there is no
chemical difference from a normal person, and even if the action or compound ingested is immediately injurious rather than pleasurable. Although many
forms of the former version of chemical dependence are fairly easy to uderstand, this version is much more difficult to get a handle on the
biochemistry, and particularly difficult to treat chemically.
Which is addiction and which is dependence? Both of those terms come with their own baggage, and have risen and fallen in popularity, each being used
at one time or another to cover the entire field of addiction/dependence.
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fledarmus
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Quote: Originally posted by CrimpJiggler ![](images/xpblue/lastpost.gif) | Quote: Originally posted by GreenD ![](images/xpblue/lastpost.gif) | maybe a bit off subject, but a bi-phenyl molecule would be planar? or would the two phenyl's have some angle of rotation about the phenyl-phenyl bond?
|
I assume they'd be free to rotate. Forming the new methylene bridge would lock the molecule into a single conformation, probably a planar one since
that would spread the atoms furthest away from each other. |
Usually a biphenyl system is not planar - it is twisted so that the ortho hydrogens do not run into each other, even though this removes any
conjugation between the phenyl rings. If you put substituents larger than protons in the ortho positions, you can actually lock biphenyl systems into
specific separable chiral conformations - this is one version of axial chirality, where you have chiral compounds with no chiral center.
Bridging the ortho positions allows the benzene rings to be closer to a planar system, now usually bent slightly towards the bridged side to allow a
little more room for the unbridged ortho hydrogens while still allowing conjugation across the connection between the phenyl rings. These compounds
are typically more stable than the corresponding non-bridged biphenyls.
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