Questions tagged [organometallic-compounds]
For questions relating to organic compounds which contain a bond between a carbon atom and a metal.
199
questions
9
votes
1answer
204 views
How does cyclopentadienyl anion act as reducing agent?
I am a second year university student, so I'm afraid my chemistry isn't great. I am looking for an explanation of how the $\ce{Cp-}$ anion acts as a reducing agent.
To contextualise - in a simple ...
0
votes
1answer
50 views
Redox reaction of cycloheptatriene ligand
The reaction I really don't understand is the second one which produces the cycloheptatriene ring with a positive charge. The only thing I can think of is that the hydrogen is being ejected and ...
1
vote
0answers
16 views
Zetasizer - How can the Z-average mean be lower than all intensity measurements?
I recently used a Malvern Zetasizer on samples of Au nanoparticles in order to determine the size of the particles (we are looking for significant shifts in particle size between samples, and as such ...
0
votes
0answers
28 views
Why is the synthesis of graphene through alkyne trimerization not viable?
I have been looking for a rationale on this as massive polycyclic aromatic hydrocarbons have been synthesized this way, and with Graphene just being an indefinite expansion of aromatic rings, this has ...
0
votes
0answers
246 views
Advantage of Ir-based vs Alq3 OLED material, is quantum yield more important over the cost?
This Wikipedia page https://en.wikipedia.org/wiki/OLED#Material_technologies mentions a couple of molecules that are used for OLED.
The Ir-based compound has ~ 100% quantum efficiency, while Alq3 may ~...
2
votes
1answer
56 views
How to "draw" a coordination bond (dashed bond) in MOLFILE?
How can we "draw" a coordination bond (dashed bond) in MOLFILE?
I cannot find a bond property or option that would allow me to choose such a thing.
So many drawings of organo-metallic ...
1
vote
0answers
29 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 ...
3
votes
0answers
81 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 ...
6
votes
1answer
164 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 ...
3
votes
2answers
73 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?
1
vote
0answers
30 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 ...
4
votes
1answer
71 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
0answers
76 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?
7
votes
1answer
155 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.). ...
2
votes
1answer
173 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
votes
1answer
90 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 ...
-4
votes
1answer
79 views
Why are tri-organotin compounds so toxic? [closed]
Organotin compounds (organostannane chemistry) are compounds with the tin-carbon bond and some of them(specifically the tri-organo ones) are as toxic as cyanide. Why is this though as I don't really ...
3
votes
0answers
72 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 $\...
2
votes
1answer
118 views
Do organopolonium compounds exist?
Analogues of alcohols exist for all the heavier Group 16 elements, namely sulfur, selenium, and tellurium. Would polonium also be able to form a "polonol" like $\ce{CH3PoH}$?
3
votes
0answers
31 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(...
2
votes
0answers
24 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 ...
3
votes
0answers
38 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 ...
5
votes
0answers
43 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 ...
0
votes
0answers
27 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
0answers
63 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 ...
5
votes
0answers
31 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 ...
4
votes
0answers
45 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}...
6
votes
1answer
549 views
Nature of a1g Molecular Orbital Interactions in Ferrocene
While learning about ferrocene I've come across this molecular orbital diagram.
What particularly confused me is the nature of the a'1g orbital. My professor taught that a'1g and e2g are considered ...
1
vote
0answers
43 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 ...
1
vote
1answer
204 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 ...
2
votes
0answers
56 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 ...
-1
votes
1answer
61 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?
4
votes
1answer
953 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 ...
4
votes
0answers
77 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 ...
0
votes
1answer
222 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,...
0
votes
0answers
62 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
1answer
190 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
vote
0answers
375 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
0answers
67 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.
8
votes
1answer
224 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 ...
-2
votes
1answer
70 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
4
votes
0answers
47 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 ...
2
votes
1answer
233 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-...
2
votes
0answers
35 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 ...
0
votes
1answer
112 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 ...
2
votes
0answers
93 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 ...
3
votes
1answer
176 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 ...
1
vote
1answer
396 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
1answer
769 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{...
6
votes
1answer
375 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. ...
