Questions tagged [organometallic-compounds]
For questions relating to organic compounds which contain a bond between a carbon atom and a metal.
226
questions
17
votes
3
answers
26k
views
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 ...
1
vote
0
answers
39
views
Can molecular systems display negative magnetic susceptibility of a higher magnitude than bismuth?
Bismuth has the biggest value when it comes to a negative magnetic susceptibility than all other elements, ignoring superconductors, as they would have a value of -1.
Yet, when tables displaying ...
- 699
3
votes
0
answers
307
views
Driving force in Corey-House reaction
In my textbook of organic chemistry by francis carey 11th edition, the Corey-house synthesis is elaborated on in the topic of organocopper reagents. It is mentioned that as the R-X alkyl halide is ...
- 111
7
votes
1
answer
477
views
Effect of metal identity on CO bond length in carbonyl complexes
In organometallic carbonyl complexes, a back-donation effect occurs: the σ molecular orbital of CO yields electron density to an orbital of the appropriate metal atom, and in turn, a d orbital of ...
- 37.7k
3
votes
2
answers
186
views
Can a Grignard reagent form magnesium halide with an alkyl halide? [duplicate]
$$\ce{RMgX + R'X' -> RR' + MgXX'}$$
Is this reaction possible?
I am not able find any reference to it in the books that I have. Anyone has a reference?
- 25.6k
2
votes
1
answer
1k
views
Reaction of acyl chloride with excess Grignard reagent
I have a reaction to which I must find the majority organic product.
I think I found the correct product but the fact that the reaction takes two moles of propylmagnesiumbromide confuses me a bit. I ...
- 3,121
1
vote
0
answers
33
views
Does concerted oxidative addition follow first-order kinetics?
So my professor for organometallic chemistry described the different mechanisms for oxidative addition and in talking about the concerted mechanism he said that it had first order kinetics. I find ...
- 5,675
8
votes
1
answer
1k
views
How to interpret the relation between CO stretch frequencies and backbonding strength for polycarbonyl compounds?
I am working on a series of octahedral complexes of the type $\ce{[M(CO)2(CH3)X3]-}$ where $\ce{M} = \ce{Co}, \ce{Rh}, \ce{Ir},$ and $\ce{X}$ is a range of ligands (halide, cyanide, nitrosyl, etc.). ...
5
votes
1
answer
183
views
Why is the trans-effect of nitrile ion (cyanide) weaker than acetonitrile (methyl cyanide) in octahedral chromium complexes?
I was reading a paper which built a series of trans-philicity (a term they coined to indicate both kinetic trans-effect and thermodynamic trans-influence) from extensive calculations. And I found that ...
4
votes
0
answers
85
views
What does pentamethylarsenic smell of? [closed]
Trimethylarsine smells of garlic. According to Wikipedia, pentamethylarsenic smells like pentamethylantimony but I can't find the smell of that anywhere.
What does pentamethylarsenic smell of?
- 4,545
3
votes
1
answer
110
views
Siiloxane polymer experiment
I believe the first reaction would be a substitution of $\ce{SiMe3}$ for $\ce{I}$ and creating $\ce{SiMe3Cl}$.
The second process I think would involve the $\ce{Mg}$ removing the two $\ce{Cl}$ and ...
3
votes
0
answers
206
views
Why is the 2-bond (Sn-H) coupling constant larger than the 3-bond Sn-H coupling constant for tetraethyltin?
I was looking at the NMR spectrum of tetraethyltin [$\ce{Sn(CH2CH3)4}$], and found that the $\ce{Sn-H}$ coupling constant between $\ce{Sn}$ and $\ce{CH2}$ is larger than that between $\ce{Sn}$ and $\...
- 5,675
3
votes
0
answers
58
views
Why can zinc porphyrins assume 5 coordinate geometries?
It has been reported that 5-coordinate geometries are possible and stable for Zn(II) porphyrin complexes. How do these complexes form and why are they stable when other 5-coordinate geometries of Zn(...
- 131
2
votes
0
answers
31
views
High kinetic basicity of alkoxides compared to alkyls
I'm reading something at the moment where they state:
This reagent has enhanced basicity as it benefits from the high kinetic basicity of alkoxides compared to alkyls.
This is in the context of ...
- 5,675
3
votes
0
answers
52
views
Reactivity of unsaturated organolithium compounds
I'm particularly looking in the context of alkyl lithiums compared to vinyl-lithiums and alkynyl-lithiums.
Why is it that shifting from sp3 to sp2, and even further to sp carbanions, reduces the ...
- 4,545
5
votes
0
answers
60
views
Why transition metal catalyzed [2+2]cycloaddition reactions allowed?
As you know, cycloaddition reactions which (4n)π electrons are involved in such as [2+2]cycloaddition are forbidden in normal organic reactions, but transition metal catalyzed [2+2]cycloaddition ...
- 123
0
votes
0
answers
182
views
Why does π-backbonding in a metal-carbonyl complex lead to a decrease in C-O bond strength?
I understand that π-backbonding in this complex involves the σ-donation of carbonyl to an empty d orbital of the metal, and the π-donation of the d electrons of the metal to the π* MO of the carbonyl. ...
0
votes
0
answers
143
views
The role of PIDA in C-H activation reactions
PIDA ((Diacetoxyiodo)benzene) is a hypervalent iodine(III) compound that acts an attractive oxidizing agent in most of the transition metal catalyzed reactions. Can someone explain me the mechanism of ...
- 51
5
votes
0
answers
34
views
Is it possible to do Cobalt catalyzed directing group asisted meta C-H functionalization of arenes
Directing Group assisted Pd catalyzed (sp2)meta-C-H functionalization has a growing attention in recent years.
In addition, few examples can be found for meta-C-H functionalization via Rhodium. I am ...
- 22.4k
4
votes
0
answers
85
views
Aluminium isopropoxide electronic structure
From Wikipedia:
A tetrameric structure of the crystalline material was verified by NMR spectroscopy and X-ray crystallography. The species is described by the formula $\ce{Al[(μ-O-i-Pr)2Al(O-i-Pr)2]3}...
- 400
1
vote
0
answers
133
views
What is the proper use of the term "pi-donor ligand"?
Robert Crabtree's The Organometallic Chemistry of the Transition Metals (7e) describes a pi-donor ligand as being a pi-donor "as a result of the lone pairs that are left after one lone pair has ...
- 2,000
1
vote
1
answer
318
views
Can copper sulfate react with terpenes (such as limonene and terpinenes) at room temperature?
I am just wondering, can I make a metalorganic or organometallic complex of copper and limonene/terpinene/phellandrene in the form of lime oil? If so, what is the formula of the complex formed? I ...
- 57.1k
2
votes
0
answers
766
views
How do you optimize an organo-metalic compound containing cerium in in Gaussian?
I am trying to perform optimisation of the molecule attached. I need to get partial charges and frequencies. The issue is that it doesn't converge with following input:
...
2
votes
0
answers
65
views
Can someone help with the nomenclature of this metal complex. MarvinSketch is giving me trouble
I’m trying to get a name for the structure above using MarvinSketch for my undergraduate senior thesis. This is the first time I’ve had to draw a metal complex in MarvinSketch, and I’m having trouble ...
- 29
-1
votes
1
answer
112
views
Weinreb ketone synthesis [closed]
For this problem, Can I use weinreb ketone synthesis? I found the product but not sure it is the right one
If the amide react with either R1-Mgbr or R2-Li,
then it produces the ketone?
- 364
4
votes
1
answer
2k
views
Wittig reaction in presence of carboxylic acids
The following reaction came in a recent test:
According to this reaction, the acidic hydrogen would protonate the ylide, and the standard wittig reaction would not take place. This source agrees with ...
- 22.4k
11
votes
2
answers
20k
views
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 ...
4
votes
0
answers
129
views
Metal coordination in enzymes: What type and number of bonds form between amino acid residues and Fe(II)?
My understanding: Transition (d-block) metals, as found in intracellular proteins, are limited to about 10 elements including amongst others Fe, Ni, and Cu. Due to the reductive environments inside ...
- 908
0
votes
1
answer
643
views
Preparation of Grignard reagent. Free radical rearrangement
Mechanism of formation of Grignard Reagent
$$\ce{R-X + ^.Mg^. ->[\text{r.d.s.}] R^. + ^.Mg+X-} $$
$$\ce{R^. + ^.Mg+X- -> R-Mg+X-} $$
As the mechanism of preparation of Grignard reagent suggests,...
- 59
16
votes
1
answer
226
views
Mechanism of a gold catalyzed addition to triple bond
I needed to draw the reaction mechanism for this reaction:
So, after consulting some literature I drew this mechanism:
But, I am not sure about the last step. Does the $\ce{H+}$ just substitute the $...
- 16.6k
0
votes
0
answers
72
views
In which condition CO uses the oxygen end for bonding?
Generally Metal Carbonyl complex are formed from Carbon end. Is it possible under some specific condition that the Oxygen end is used?
(PS -I know about the structures of M-CO bonding)
3
votes
1
answer
242
views
What would be the product of following elimination reaction?
Question
Doubt
The answer is given B. But why cant it be C after all formation of cyclopropane would increase angle strain?
- 1,244
2
votes
0
answers
85
views
What is the difference between a dπ-dπ and delta bond [closed]
I have always been wondering the difference between a dπ-dπ bond and a delta bond. What are the situations that either bond is formed in overlap of two d orbitals.
- 111
9
votes
1
answer
315
views
Can ferrocene type sandwich compounds be made with fluorene?
Ferrocene will be well known to made members of this site. It consists of two cyclopentadienyl anions sandwiching an iron-II ion.
During my first year organic chemistry course (about 40 years ago) I ...
- 1,983
-2
votes
1
answer
346
views
Reaction of grignard in presence of Halogen [closed]
What happens when a Ketone say $$RCOCH3$$ on reaction with grignard reagant in presence of X2 (halogen) what happens?? Can someone please explain
- 109
4
votes
0
answers
60
views
Curtin-Hammett principle to evaluate alkene insertion
Given an unsymmetrical alkene in a simple non-stereoselective catalytic hydrogenation reaction. If one would want to investigate the nuances in the catalytic cycle of a dihydride complex leading to ...
4
votes
1
answer
233
views
What is the mechanism of this reaction?
I've been stuck with this for some time. I just don't see it. As the reactant is Pd(0), I think oxidative addition will happen to the bromine. Then I would say an insertion reaction happens. However ...
- 16.6k
3
votes
1
answer
784
views
Reason for double acylation of ferrocene only occurring with certain reagent combinations
Can anyone explain why the acylation of ferrocene produces the following results:
Ferrocene + acetic anhydride + AlCl3 ==> mono-acylated ferrocene
but:
Ferrocene + acetyl chloride + AlCl3 ==> di-...
- 57.1k
2
votes
0
answers
40
views
Are there many examples of stable, well characterised organometallic compounds of saturated hydrocarbons with beta hydrogens?
One of the first things you tend to learn in organometallic chemistry is that transition metal compounds containing beta-hydrogens are unstable (there are plenty of stable main groups ones; eg ...
- 36.1k
0
votes
1
answer
359
views
Organometallic and oxygen
I often read that reactive organometallics must be handled under an inert atmosphere because they react with oxygen in the atmosphere. This applies to grignard reagents, organolithium reagents, and ...
- 22.4k
4
votes
1
answer
3k
views
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 $6$ ...
- 37.7k
12
votes
1
answer
2k
views
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.
- 27.7k
8
votes
1
answer
31k
views
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 ...
2
votes
0
answers
203
views
Reaction mechanism of lithiated benzene and oxygen in acid
According to (1) addition of O2 in acid to lithiated benzene makes phenol.
I'm trying to deduce the mechanism, and somehow it doesn't feel right but I'm not sure.
(1) Snieckus, V. Directed ortho ...
- 71.1k
1
vote
1
answer
801
views
Triphenylphosphine (PPh3) vs. 1,2-bis(diphenylphosphino)ethane (dppe) ligand?
What about $\ce{NiCl2(dppe)}$ makes it a more efficient catalyst for Suzuki cross-coupling as opposed to $\ce{NiCl2(PPh3)2}$ or $\ce{NiCl2(PCy3)2}$? How does the dppe ligand increase the reactivity of ...
0
votes
1
answer
1k
views
What is the oxidation state of copper in Gilman's Reagent? [closed]
What is the oxidation state of copper in Gilman's reagent? In $\ce{R-Cu}$ bond the oxidation state is +1. Thus in $\ce{R-Cu-R}$ bond the oxidation state has to be +2. But if that so why positive $\ce{...
- 57.1k
6
votes
1
answer
540
views
Volatile alkali metal compounds
Most elements are or have compounds that are gases or have a significant vapor pressure at room temperature. Fluoride is a powerful tool for producing highly oxidized covalent and volatile compounds. ...
- 37.7k
2
votes
0
answers
588
views
How does electrophilic bromination with 1,2-dibromoethane work?
Hi I am trying to figure out the mechanism of a reaction containing a lithium carbanion and 1,2-dibromoethane in THF. The lithium carbanion is generated by deprotonating using LDA. Then 1,2-...
- 503
1
vote
0
answers
241
views
Why do statistical effects impact stepwise stability constants?
I have a question regarding the stepwise stability constants of metal complex formation/substitution.
My lecture notes say that if we have a metal complex, say $\ce{[MX_{6}]}$, and a substitution ...
- 68k
1
vote
0
answers
122
views
Why CO is a weak pi-acid ligand?
This question was given by my chemistry professor, but I doubt that this question is not correct.
Following the lewis definition of the acid, any molecule or atom acts as a acid if it accepts an ...
- 323