Questions tagged [organometallic-compounds]
For questions relating to organic compounds which contain a bond between a carbon atom and a metal.
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Why do Organolithium or Grignard reagents act as nucleophiles and not as bases with aldehydes and ketones
I've read entire Chapter 14: Organometallic Compounds of Francis Carey's "Organic Chemistry" but I still didn't get an answer to my question.
Quote from the book:
Because of their basicity ...
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Why do Magnesium and Lithium form *covalent* organometallic compounds?
Lithium and magnesium are Group 1 and Group 2 elements respectively. Elements of these groups are highly ionic, and I've never heard of them forming significantly covalent inorganic compounds.
Yet ...
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Inorganic chemistry reaction mechanisms
Are there well developed reaction mechanisms in inorganic chemistry like those in organic chemistry? If yes, please suggest an easy to follow reference.
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Predicting bond-strength of metal carbonyls
The metal carbonyls (and similar organometallic compounds) involve a combination of sigma bond, a pi bond and backbonding. The bond strengths under consideration are the metal-carbon bond and the ...
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Why do halogen-metal exchanges happen?
I'm trying to understand organometallic raegents but am stuck at halogen-metal exchanges.
For example if you have $\ce{PhBr + BuLi}$ you get $\ce{PhLi + BuBr}$, I don't understand why $\ce{PhBu + ...
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Reduction of alkyl halides to alkanes
For all the three parts, only methane has been given as the product in my textbook.
In 1) and 2), according to the mechanism I wrote, I get both ethane and methane as products. I think both these ...
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Reaction of Grignard reagents with esters
Suppose I have a phenyl Grignard and methyl benzoate.
If I react the two, can I expect benzophenone and a triphenylmethoxide ion as my products?
I ask because I know that Grignards react with ...
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What is the mechanism of formation of Grignard's Reagent?
What is the mechanism of formation of Grignard reagents? I couldn't find much in my book or on the Internet. This page says something which I am unable to understand. Why are the $2$ electrons in the $...
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Why do Grignard reagents react with epoxides but not THF?
THF is used as a solvent for Grignard reagents, but epoxides react with Grignard reagents. There is only a small difference between epoxides and THF, what causes the difference in reactivity towards ...
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Sodium Naphthalenide
The sodium fusion test done in the lab for the systematic identification of a given organic compound is basically fusing sodium metal in a fusion tube, and then adding the compound in a small quantity,...
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Why does magnesium form covalent bonds with carbon?
According to my professor, magnesium and lithium form covalent bonds with carbon but calcium does not. He did not elaborate.
Why is this so? The electronegativities are:
Mg — 1.31
Li — 0.98
Ca — 1
...
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Do eta-4 benzene ligands participate in Diels Alder or other cycloadditions?
While refreshing myself on denticity to answer another question, I started to read about hapticity, which is the coordination of a ligand through multiple continuous atoms. A famous case is ferrocene (...
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Negative oxidation states of Si
According to List of oxidation states of the elements, silicon has a possible oxidation state of $-4$.
Now, I've been looking everywhere for a compound that contains Si(-IV), but I cannot find any ...
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Why can't the reaction of grignard reagent with carboxylic acid give a ketone?
I understand that a Grignard reagent can act both as a base and a nucleophile.
It acts as a base in the presence of a proton source (eg: alcohols, amine, water, etc). But when reacting with a ketone ...
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How can the solid state structure of cyclopentadienyllithium be explained?
In the solid state, LiCp adopts a polymeric multidecker structure where Li atoms are sandwiched between two Cp rings (shown in this diagram from Organometallics 1997, 16 (17), 3855–3858):
If we ...
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Ketone/aldehyde synthesis from N-acylazetidines or aziridines
A common principle in organic chemistry is to make sure the product is less reactive than the starting material, to prevent overreaction. So, for example, the treatment of an ester with a Grignard ...
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What makes R-MgX a more reactive Grignard reagent than R-Cu?
What makes $\ce{R-MgX}$ a more reactive Grignard reagent than $\ce{R-Cu}$? Has it to do with solvation, bond enthalpy, electronegativity?
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Dissociation rates: trans-effect rule in square planar complexes
In lecture, the trans-effect was described.
A ligand $L^t$ with a higher trans-effect as $L$ (cis to $L^t$) leads to a faster dissociation of ligand $L^d$ (trans to $L^t$). I would expect that the ...
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Coordination number of carbon in methyllithium tetramer
According to J. D. Lee's Concise Inorganic Chemistry, the coordination number of carbon in $\ce{Li4(CH3)4}$ is $7$. But the structure of the tetramer is
Doesn't carbon have coordination number $6$ ...
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Why do heavy metals like mercury and lead have an affinity for sulfur or sulfur compounds?
Many of the heavy metals such as mercury, lead, thallium, cadmium, and arsenic exert toxic effects largely by binding to or otherwise interfering with organic sulfur compounds or groups in the body. ...
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What's the explanation for the chelate effect? [duplicate]
I got that multidentate ligands form more stable coordination complexes than monodentate ligands, but why?
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Why are organolithium and organomagnesium compounds nucleophilic in nature?
My textbook doesn't say anything about this but does say that on addition of organolithium compounds to carbon dioxide, they give ketones and not carboxylic acids like grignard reagents. This has been ...
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What makes dimethylmercury ((CH3)2Hg) so penetrative through latex and human skin?
I've read the story of Karen Wetterhahn and how she was poisoned and died from two drops of dimethylmercury that accidentally fell on her latex glove, and I was wondering what is the chemical ...
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Bonding between rings and iron atom in ferrocene
How are the 10 vertical bonds in Ferrocene (sandwich structure) connected, by what type of bonds?
What is the real structure of ferrocene? Concerning the 10 vertical extra long bonds?
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Grignards do transmetallation?
Grignards don't add to alkyl halides to create linear carbon extensions because Grignards do transmetallation rather than SN2 displacement of halide.
Is this correct?
I thought transmetallation a) ...
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Chemical function of Mg and Conjugated bonds in Chlorophyll [closed]
This question has 3 parts, each related to the title.
In biochem, we were shown the chemical structure of chlorophyll. The light-absorbing head has many carbon-rings with alternating single and ...
