Sciencemadness Discussion Board - Organometallic Chemistry

Organometallic Chemistry

thebean - 2-2-2014 at 12:08

I'm not sure that this is the right place to be posting but a thought occurred to me today that I wanted to ask about. Have any of the admins or mods ever discussed having an organometallic subforum? Or would that just belong in Organic? I personally would like it but it is quite the niche subject.

[Edited on 3-2-2014 by thebean]

forgottenpassword - 2-2-2014 at 12:26

Considering that inorganic chemistry has yet to have its own section, I can't see it happening!

Zyklon-A - 2-2-2014 at 12:46

I see nothing wrong with it (although my opinion likely matters little).

Quote:

Considering that inorganic chemistry has yet to have its own section, I can't see it happening!

I think that's because inorganic chemistry is summed up in all the other forums/sub-forums except organic chemistry.

[Edited on 2-2-2014 by Zyklonb]

Random - 2-2-2014 at 13:28

Organometallic chemistry often requires dangerous reagents and it's also a rare subject to be discussed here just as are organophosphorus compounds for example.

Most of the time when a subject that contains it appears, it is posted in organic chemistry. After all it actually is organic chemistry.

DraconicAcid - 2-2-2014 at 14:40

Quote: Originally posted by Random

Organometallic chemistry often requires dangerous reagents and it's also a rare subject to be discussed here just as are organophosphorus compounds for example.

True. I've done a lot of organometallic chemistry, and I'd never try to do any of it at home.

Quote:

After all it actually is organic chemistry.

Um...no. It isn't.

Magpie - 2-2-2014 at 20:51

Quote: Originally posted by DraconicAcid

Quote: Originally posted by Random

Organometallic chemistry often requires dangerous reagents and it's also a rare subject to be discussed here just as are organophosphorus compounds for example.

True. I've done a lot of organometallic chemistry, and I'd never try to do any of it at home.

Why not? I've done a couple Grignards in my garage lab and didn't consider them of much concern.

[<a href="u2u.php?action=send&username=bfesser">bfesser</a>: fixed mismatched BBCode tags]

[Edited on 3.2.14 by bfesser]

TheChemiKid - 3-2-2014 at 04:37

Even simpler, there are some simple organometallic ligands such as Copper Aspirinate

forgottenpassword - 3-2-2014 at 05:45

Quote: Originally posted by TheChemiKid

Even simpler, there are some simple organometallic ligands such as Copper Aspirinate

... with no organo-metallic bonds!

DraconicAcid - 3-2-2014 at 08:29

Quote: Originally posted by TheChemiKid

Even simpler, there are some simple organometallic ligands such as Copper Aspirinate

Which is neither a ligand nor organometallic.

mnick12 - 3-2-2014 at 13:27

Organometallic chemistry is awesome, and coordination chemistry is as well. They are very interesting fields of chemistry and are yet to be explored to the extent as o-chem and others. My research at school is devoted to this field, and what is being done is freakin sweet!

However I agree that certain reactions should be left to professionally equipped labs. Grignards are probably the farthest I would go in a home lab, I would never use anything like sodium triethylborohydride or methyllithium in a home lab. With that being said there are some very fulfilling experiments that can be conducted at home, personally I think coordination chemistry has some of the prettiest reactions around! Most ligand synthesis is pretty straight forward, and making chelates is also pretty easy.

Random - 3-2-2014 at 13:42

Quote: Originally posted by DraconicAcid

Quote:

After all it actually is organic chemistry.

Um...no. It isn't.

Aside from a metal atom, the other stuff is mainly organic. Just as is methanethiol for example. Not completely same though, I agree.

Also grignard reagents are pretty basic stuff from what I have read, when you get into the real stuff then it hardly gets easily done. Pyrophoric chemicals that can basically burn you can be a common sight for example.

[Edited on 3-2-2014 by Random]

[<a href="u2u.php?action=send&username=bfesser">bfesser</a>: fixed mismatched BBCode tags]

[Edited on 4.2.14 by bfesser]

DraconicAcid - 3-2-2014 at 13:54

Quote:

Aside from a metal atom, the other stuff is mainly organic.

That's a bit like saying that, apart from the hydrogen ion, perchloric acid's just a weak base.

Quote:

Also grignard reagents are pretty basic stuff from what I have read, when you get into the real stuff then it hardly gets easily done. Pyrophoric chemicals that can basically burn you can be a common sight for example.

Grignard reagents are fairly harmless, yes (okay, pyrophoric and extremely basic, but simple enough to work with). But things like diethyl zinc, nickel tetracarbonyl, ferrocene, cyclopentadienyliron dicarbonyl dimer...these are what I consider *real* organometallic compounds, and I'm not having them at home (well, okay, I wouldn't mind having a sample of ferrocene to display, but not the others).

BromicAcid - 3-2-2014 at 14:43

Quote: Originally posted by DraconicAcid

But things like diethyl zinc, nickel tetracarbonyl, ferrocene, cyclopentadienyliron dicarbonyl dimer...these are what I consider *real* organometallic compounds, and I'm not having them at home (well, okay, I wouldn't mind having a sample of ferrocene to display, but not the others).

When I was doing chemistry at home I made a number of organometallic compounds, diisopropyl lead, methyl lithium, and sodium napthalide spring to mind immediately. There are plenty that can be done safely at home. As for things like dimethyl zinc I would feel comfortable working with those at home only one the 1-4 gram scale. Wearing proper flame resistant PPE that kind of quantity is limited to what kind of damage it can do, provided you don't have bottles of solvent or combustible building materials laying around.

These are all *real* organometallics, inherent danger does not an organometallic make. Dimethylmercury isn't pyrophoric at all afterall

The real question though is, is there a need for such a subforum? Are organometallic posts clogging your threads in the other sections? If you want to sift through all the threads on the forum (takes about 8 hours if you're quick about it) and take note of the threads involving organometallic chemistry then compare that to the Computational Models and Techniques sub-forum (which is pretty devoid of traffic) you might be able to make a case. But really I think organometallic fits in nicely where ever you put it.

woelen - 4-2-2014 at 00:28

Organometallic chemistry certainly is not the easiest thing to do at home (there are a few exceptions). In many cases, you need to exclude air and some of the experiments require special solvents, which are not easy to get. Many ligands are very sensitive (air/moisture) and hardly can be kept around in a normal home-setting (e.g. they must be stored under argon or nitrogen and never ever may come in contact with air, so all processing must be done in a special box).

I like to read about all those weird and surprising complexes, but I feel no need to experiment with them at home, simply because it requires too much apparatus and too many very special chemicals. I think that for the home chemist there is a lot of coordination chemistry, which can be done at home, using water or other common solvents (e.g. ethanol, methanol, acetone, certain acids) and which also has interesting properties.

thebean - 18-2-2014 at 17:25

Quote: Originally posted by TheChemiKid

Even simpler, there are some simple organometallic ligands such as Copper Aspirinate

Copper aspirinate is neither an organometallic compound (It lacks the carbon-metal bond) or a ligand. What you are describing is sometimes called a metalorganic.

Acidum - 24-2-2014 at 13:14

First - Organometallic chemistry, as interesting as it is, does not need subforum, as it is perfectly fitted at Organic chemistry subforum and does not have that much homemade examples to separate it because of numerous posts.
Topics with clearly understandable titles are all we need...

Second - There seems to be ongoing conflict between org and inorg chemists about organometallic definition... As organic chemist, I (we if we count all my colleagues) consider compounds such as BuLi, Grignard reagents, diethyl zinc, Li-diisopropylamide, allkoxides, etc... to be organic, organometallic. Salts and complexes, such as CaCO₃, Ni(CO)₄, copper acetylsalicilate, sodium acetate, etc... are considered as inorganic.

...just my couple of cents...

DraconicAcid - 24-2-2014 at 16:56

Quote: Originally posted by Acidum

Second - There seems to be ongoing conflict between org and inorg chemists about organometallic definition... As organic chemist, I (we if we count all my colleagues) consider compounds such as BuLi, Grignard reagents, diethyl zinc, Li-diisopropylamide, allkoxides, etc... to be organic, organometallic. Salts and complexes, such as CaCO₃, Ni(CO)₄, copper acetylsalicilate, sodium acetate, etc... are considered as inorganic.

...just my couple of cents...

To be considered organometallic, there needs to be a covalent bond between a metal and carbon. Lithium diisopropylamide and alkali metal alkoxides don't have these. Neither do calcium carbonate, copper acetylsalicylate, sodium acetate or potassium cyanide.

Diethyl zinc and nickel tetracarbonyl are definitely organometallic.

Alkyllithiums and Grignards are borderline- most of the chemists I know would consider them organometallic, but leave them to the organic chemists.

Many inorganic chemists will not consider cyanide complexes to be organometallic, considering cyanide to be a pseudohalogen, not really an organic ligand.

turd - 26-2-2014 at 00:58

Quote: Originally posted by DraconicAcid

To be considered organometallic, there needs to be a covalent bond between a metal and carbon.

That's what Wikipedia says. But if you open an issue of Organometallics you will find that many of the common ligands used in organometallic chemistry do not coordinate via C.

Quote:

[N]ickel tetracarbonyl [is] definitely organometallic

Not as definitely as you think. Yes, the structures of Ni(CO)₄ and Fe(CO)₅ were published in Organometallics, but they are archived in the ICSD (http://www.fiz-karlsruhe.com/icsd.html) and I'm quite sure many organometallic chemists consider metal carbonyls as precursors to rather than "real" organometallics.

The whole differentiation between organic and inorganic chemistry is arbitrary anyway and I don't think that there is something that could be called a "conflict". Holleman-Wiberg for example lists mellitic anhydride as an inorganic compound, because it does not have C-H bonds. *shrug*

DraconicAcid - 26-2-2014 at 10:07

Quote: Originally posted by turd

That's what Wikipedia says. But if you open an issue of Organometallics you will find that many of the common ligands used in organometallic chemistry do not coordinate via C.

Quote:

[N]ickel tetracarbonyl [is] definitely organometallic

Your last statement surprises me. I did a PhD and a post-doc with organometallic chemists, and never heard that opinion from any of them. Then again, I haven't seen an issue of Organometallics in nearly ten years...

bfesser - 26-2-2014 at 11:51

Regardless of what we choose to classify as Organometallics discussion, there's simply not enough activity to justify the creation of a new forum. Hell, we hardly get enough activity in the <a href="forumdisplay.php?fid=10">Organic Chemistry</a> forum—most of the posts end up in Beginnings. Any genuine organometallics threads we've seen so far fit nicely into the Organic forum.

It's important to note that this is only my personal opinion based on my own observations of forum activity. It's neither my decision to make, nor have we seen the opinions of other mods and the admins.

turd - 27-2-2014 at 09:25

Quote: Originally posted by DraconicAcid

On the other hand it surprises me that anyone would consider CO as definitely organic. A corner-case, sure, but definitely? Because it really does not look like what you would expect from an organic compound (C-C bonds, C-H, bonds, tetravalent C, bivalent O).

Quote: Originally posted by bfesser

Regardless of what we choose to classify as Organometallics discussion, there's simply not enough activity to justify the creation of a new forum. Hell, we hardly get enough activity in the <a href="forumdisplay.php?fid=10">Organic Chemistry</a> forum—most of the posts end up in Beginnings. Any genuine organometallics threads we've seen so far fit nicely into the Organic forum.

Agreed. If it's ligand synthesis it fits nicely into organic chemistry, if it's complex formation with a common ligand, it goes into general chemistry. No point in fragmenting the forum.

DraconicAcid - 27-2-2014 at 09:59

Quote: Originally posted by turd

Quote: Originally posted by DraconicAcid

Actually, I don't consider CO to be organic; I just consider carbonyls to be organometallic. That seems counterintuitive, I know...

turd - 28-2-2014 at 06:26

Quote: Originally posted by DraconicAcid

Actually, I don't consider CO to be organic; I just consider carbonyls to be organometallic. That seems counterintuitive, I know...

Yes, that is a bit counterintuitive.

Just to get this straight: Suppose you have a pyridine based neutral pincer L and a bivalent metal M. According to your definition the neutral complex [MLCl₂] is not an organometallic, but the cationic [ML(CO)₂]²⁺ is organometallic, not because of the organic ligand L, but because of the inorganic molecule CO? I will have to think about that. Because so far it doesn't make much sense to me...

[Edited on 28-2-2014 by turd]

DraconicAcid - 28-2-2014 at 08:38

Quote: Originally posted by turd

Quote: Originally posted by DraconicAcid

Actually, I don't consider CO to be organic; I just consider carbonyls to be organometallic. That seems counterintuitive, I know...

Yes, that is a bit counterintuitive.

It's all in the metal-carbon bond. If you count a pyridine complex as organometallic, then you've have to count ethylenediamine complexes, EDTA chelates and acetates as organometallic, and that would be ridiculous.