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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Bridging Hydride Covalent Model Electron Count - Hartwig
How can a bridging hydride be considered a 3 electron donor in the covalent model for electron counting?
On page 3 of John Hartwig's "Organotransition metal chemistry" textbook [1], he lists ...
4
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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}...
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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 ...
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27 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 ...
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1answer
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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 ...
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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 ...
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1answer
49 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?
3
votes
1answer
174 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
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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
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1answer
63 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,...
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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)
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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?
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174 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
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0answers
51 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
192 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 ...
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1answer
26 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
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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
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1answer
87 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
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0answers
31 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 ...
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1answer
50 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
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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
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1answer
114 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 ...
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1answer
171 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
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1answer
398 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
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1answer
291 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. ...
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157 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-...
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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 ...
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83 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 ...
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44 views
Organometallic Synthesis: Cp2Ti(I)Me from TiCl4
I've been working on this synthesis question for a couple days but I'm a little stuck. The question is:
Using only $\ce{TiCl_{4}}$, $\ce{NaCp}$, $\ce{PhLi}$, $\ce{MeI}$, and $\ce{EtMgBr}$, ...
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1answer
107 views
Why does cyclobutadieneiron tricarbonyl behave aromatically?
It is said that $\ce{(\eta^4-C4H4)Fe(CO)3}$ can undergo electrophilic substitution reactions. Therefore, it displays aromaticity.
For the iron atom, it has $8$ electrons in its outer shell initially ...
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IRC analogue of conical intersections and minimum energy crossing points?
In my project, there are some spin forbidden organometallic reactions that involves both the triplet minima and singlet transition state (TS). Using the penalty method in qchem as well the method of ...
2
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1answer
348 views
Why there are more examples of carbonylate anions than metal carbonyl cations?
I know that metal carbonyl complexes that do not follow EAN rule or 18 electron rule try to achieve that by gaining electron (forming carbonylate) or loosing electron (forming carbonyl cations). But ...
0
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1answer
83 views
Why has nature evolved to put a porphyrin (i.e. chlorophyll) as the chromophore in a leaf? [closed]
I'm stumped by this question:
Why has nature evolved to put a porphyrin (i.e. chlorophyll) as the chromophore in a leaf?
I've thought that it might have something to do with how sun emits light ...
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Further reading on photoconductivity of hemoglobin
I recently ran into this paper which describe experiments that confirm that hemoglobin is photoconductive. Finding this fact as incredible, I wanted to read up more on photoconductive properties of ...
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Why doesn't Grignard reagent attack alkyl halides [duplicate]
When we add magnesium to
alkyl halide, Grignard reagent is formed. $$\ce{R-X + Mg -> RMgX } $$ It is highly nucleophilic in nature. Now at this time the electrophilic alkyl halide is also present ...
2
votes
1answer
378 views
How does 1-bromo-2-fluorobenzene react with lithium amalgam? [closed]
How does this organometallic reagent react with 1-bromo-2-fluorobenzene? Does it react like Grignard reagent? If the product of this reaction is then reacted with furan, what will be the final product?...
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On the stability of methyl mercury
Question: Given that $\ce{Zn, Hg}$ are in the same group, how to explain that $\ce{Hg(CH3)}$ is stable but $\ce{Zn(CH3)}$ is unstable and $\ce{Hg(CH3)Cl}$ is stable? $\ce{Hg(CH3)}$ seems to have an ...
3
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1answer
792 views
Will ferrocene undergo electrophilic aromatic substitution?
Ferrocene has two structure 1 and 2.It is bonded to an aromatic ion cyclopentadienyl anion.Aromatic species such as benzene , cyclopentadienyl anion undergo electrophilic aromtic substitutions.
Then,...
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Alkyl insertion with cobalt and CO
Reaction of $\ce{(Cp)Co(Me)2(CO)}$ in the presence of excess $\ce{CO}$ yields two different organic products, $\ce{A}$ and $\ce{B}.$ The only metal-containing product is $\ce{(Cp)Co(CO)2}.$ The IR ...
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Will lead bind to dissolved polymer (Kapton) monomers?
We are attempting to determine the concentration of lead impurities in Kapton. Essentially we need to extract lead in the tape polymer Kapton (structure seen below);
The amount of lead in the tape is ...
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Electron-donating trends for ligands bound to metal complexes
Imagine an inorganic complex with a bunch of terminal ligands. All else the same, would $\ce{F-}$ or $\ce{Br-}$ ligands be more electron-donating and why?
Of course, in terms of $\mathrm{p}K_{\mathrm{...
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Can pi backdonation occur on non-metal centers?
The common example of back-donation is the interaction of a CO molecule with a metal center (d-orbitals) on a surface.
Can a similar mechanism occur between CO and a non-metal center, like oxygen on ...
2
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1answer
188 views
N-heterocyclic carbene metal complexes. Question about the delocalization of the nitrogen lone pairs
I am wondering why nitrogen lone pairs are delocalized in NHC metal complexes. What I can think of is, when complex is formed, plus charge is formed on the carbon atom and therefore delocalization ...
6
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1answer
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Why do aromatic compounds have an upfield shift upon coordination to metals?
Why do aromatic compounds have an upfield shift upon coordination to metals e.g. ferrocene? The 1H NMR shows a single environment at ~4.1 ppm. This is in contrast to the usual aromatic shift of ...
4
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1answer
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Grignard Reagent in THF vs in Diethyl ether
While learning about the Grignard reagent I was taught this by my teacher, but I couldn’t justify why it was so..
I cannot see how Grignard reagent would react differently in basically an ethereal ...
2
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1answer
396 views
Is an alcohol-based spray cleaner ok for cleaning an aluminum heat exchanger?
Simple alcohols such as ethanol can, apparently, corrode aluminum. However, this corrosion reaction seems to be very slow at room temperature and below. Is an ethanol based, non-foaming spray cleaner, ...
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Why does LDA solution gradually turn dark brown?
LDA (lithium diisopropylamide) solution in THF/hexane gradually turns red-brown liquid. Especially commercially available one is extremely dark red-brown. What makes it brown?
I've searched online ...
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442 views
Reaction of grignard with beta Keto ester [closed]
A reaction takes place between $\ce {CH3COCH2COOC2H5}$ with 4-chlorophenyl magnesium bromide, followed by acidic work-up. What will be major product of the reaction? Would the product be the same as ...
2
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0answers
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How to calculate the magnetic exchange coupling in a charged radical complex?
I have a neutral complex with two magnetic centers. For this case it is easy to calculate the exchange coupling as the broken symmetry state is converged properly. But when I am making the complex ...
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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 ...