Questions tagged [organometallic-compounds]
For questions relating to organic compounds which contain a bond between a carbon atom and a metal.
210
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Is associative ligand exchange possible with octahedral complexes?
Can associative ligand exchange produce an octahedral intermediate as long as the initial complex has 16 electrons (unsaturated)?
Not sure. all I ever see is a square planar turning into a trigonal ...
16
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1
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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 $...
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Looking for a low boiling point solvent for MAPI precursors (Lead Iodide (II) and Methylammonium Iodide) [closed]
Things I have thought of till now:
Acetonitrile with HI additive
Acetonitrile with DMSO additive
The problem with the first would be that HI is in an around 55% aqueous solution and water doesn't ...
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How to name this quintuply-bonded chromium dimer?
Depicted below is a chromium compound with a metal–metal quintuple bond. It boasts two identical bridging ligands, derivatives of 1,3-diphenylbenzene. The aim of this question is to figure out
the ...
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0
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C-O bond strength in metal carbonyls [duplicate]
The metal carbonyls (and similar organometallic compounds) involve a combination of a $\sigma$-bond, a $\pi$-bond and backbonding. The bond strengths under consideration are the metal-carbon bond and ...
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17
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Are there any significant uses of the compound formed by magnesium and anthracene?
In an unusual reaction, magnesium reacts with anthracene in THF to form a grignard-like compound called, prosaically, magnesium anthracene:
I remember using it briefly in the 1980s. At the time there ...
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How to reconcile conflict between assumed oxidation state and the most stable multiplicity from electronic structure calculations?
Consider either of the small, neutral molecules containing two Zn atoms below. If I were to determine the oxidation state of Zn from this molecule, I would formally assume each Zn to be Zn(I) in order ...
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Which complex is the most stable?
Between $\ce{[Rh(Ph2PCH2PPh2)3]^{3+}}$ and $\ce{[Rh(Ph2PCH2CH2PPh2)3]^{3+}}$, which one is the most stable thermodynamically? I think it's about the size of the chelate ring effecting their stability, ...
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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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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 ...
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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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Complexation of hydroxy chalcone oxime with metal [closed]
Does the complexation of 2-hydroxy chalcone oxime (below) with a metal require any catalyst? Is the complexation pH sensitive?
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What is the systematic name of ammonium bisoxalato cuprate (II)? [closed]
What is the systematic name of ammonium bisoxalato cuprate(II)?
I already tried $\ce{(NH4)2[Cu(C2O4)2]^{2+}}$ but i am uncertain if that answer is correct.
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How are Grignard reagents stable in an ethereal solution? [duplicate]
I have heard of the leveling effect, which mentions that highly basic ions cannot exist in a solvent if it's acidity is high enough to be deprotonated by the base.
Considering that, check out the ...
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1
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Why does a smaller bandgap correlate to increased absorption of visible light?
I am currently involved in a project on metal organic frameworks in my AP chemistry class, and specifically their applications in $\ce{CO2}$ reduction into formate. All the explanations we can find on ...
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Is it safe to lyophilize/Freeze-dry a chelated compound?
I have a compound that consists of a metal ion chelated by a linear organic structure with assorted moieties in aqueous medium. I'd like to dehydrate this mixture fully to get solid product, but ...
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Is the term "heteroatom" reserved for exclusive elements?
From my experience, typically in organic chemistry, the implication of "hetero-atom" in some molecule is understood as B, N, O, S, P or a halogen -- or any nonmetallic element, perhaps.
If one ...
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Noyori hydrogenation and the Curtin–Hammett principle
My question is relating to how the Curtin–Hammett principle applies to homogeneous hydrogenation using chiral ligands.
Figure 0: An example of a quadrant diagram used as a mnemonic to predict the ...
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CO stretching frequency band in the IR spectrum for tetracarbonylnickel and tetracarbonylferrate(II)
A past exam question says:
With reference to the main bonding interactions between a transition
metal and a terminal $\ce{CO}$ ligand, explain whether you would expect to
observe a lower $\ce{...
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11
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Terminal Alkyne in Suzuki Coupling
I've done a very similar reaction to the one below but by TLC I observe only starting materials. It's super clear that nothing else is going on. Conditions: K3PO4, Pd(dppf)Cl2, dioxane/water, heat to ...
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Why does magnesium prefer to insert into C–Br bonds over C–Cl bonds?
In the formation of a Grignard reagent from a compound possessing both bromine and chlorine, magnesium preferentially inserts into the C–Br bond over the C–Cl bond. For example, the formation of a ...
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Synthesis of a tungsten carbene bromide from [CpW(CO)3]-
I'm currently working through past test and exam papers in order to prepare for my organometallic test at the end of the month, but unfortunately I've gotten stuck on the following question.
Since I ...
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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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Grignard Reagent R group [closed]
Can the R group of a Grignard reagent (RMgX) be an alkene?
Also what groups can't R be?
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Does 30% hydrogen peroxide eat away at platinum?
if I soaked a platinum dish with 30% hydrogen peroxide, will it eventually eat away at it?
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Wilkinson's catalyst: why this structure?
I wonder how the structure of Wilkinson's catalyst contributes to its catalytic properties. For example, what role do the phosphine ligands play? What properties make Rh the best TM centre?
Thank ...
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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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Selectivity of olefin cross-metathesis reaction
I'm looking at the reaction shown below which uses a ruthenium catalyst:
I am confused because the ruthenium catalyst which is used in the reaction should be Z selective due to the features on the ...
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Are there any stable complexes where an (N-unsubstituted) imine is bound eta^2 to a (late) transition metal?
I've been looking for an example of a stable complex where a $\ce{C=N}$ is coordinated $\eta^2$ to a (late) transition metal, but could not find any. Do they exist at all?
For $\ce{C=C}$ there are ...
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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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Treatment of ketones with excess Tebbe reagent
The reaction in black below was presented in a set of lecture notes as an example of the use of the Tebbe reagent, however it's not immediately obvious (to me, at least) that the product should be the ...
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I found transition states (TS), but calculations aren't supported by experiment. Do I look for more TSs or somewhere else?
I'm using Gaussian to investigate a catalyst system.
Experimental evidence showed that one of three analogues (R = phenyl, Ph), yielded a benzosultam
when treated with 2,4,6-...
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Cycloaddition of Silyl Dienol Ethers with Sodium Bromodifluoroacetate: What's the scope?
I have recently came across this article "Copper(I)-Catalyzed [4 + 1] Cycloaddition of Silyl Dienol Ethers with Sodium Bromodifluoroacetate: Access to
β,β‐Difluorocyclopentanone Derivatives". (Org. ...
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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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660
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Formation of pi-allyl Pd cation complex
(from pg. 1334 of Clayden Organic Chemistry 1st ed.)
In the above reaction catalyzed by Pd, I'm not exactly sure what's going on at the second step. It says in the book that Pd is using its electrons ...
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2
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Best reagents state for air free chemistry. Choosing halide for grignard synthesis
I am planning to synthesize a grignard and I have a choice between the iodo or chloro aryl halide. The iodo is a solid and the chloro is borderline. For my previous reaction I melted the chloro and ...
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Reaction of (RhCp*Cl2)2 with butadiene
This is the reaction that took place:
This is the information from the $\ce{^1H}$ NMR spectrum:
$$\begin{array}{|c|c|c|}
\hline
\delta \textbf{ / ppm} & \textbf{Relative intensity} & \...
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Reagents used to prepare organic ICP standards, from scratch
I am trying to figure our how I can make my own calibration standards for organic ICP analysis. I assume that I need organometallic compounds to mix with base-oil/mineral-oil to prep the standards, ...
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Iodine/ Magnesium Exchange reaction?
Traditional Grignard reagents are made by reacting alkyl halide with Magnesium metal. However, the preparation and scope of their application have been limited because of low functional group ...
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Total valence electrons in a rhodium complex
How many valence electrons does the following metal complex have?
I have read that benzene donates 6 electrons to a transition metals valence electrons. Rh has 9 from itself, and H and Cl add 1 each; ...
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Why doesn't beta hydride elimination happen in alkenyl/aryl halides?
Beta hydride elimination is an important reaction in organometallic chemistry:
This reaction prohibits the use of saturated alkyl halides in coupling reactions, because it can take place after ...
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What happens to the Lithium halide salt when reacting Lithium metal with alkyl halides?
In organic chemistry, I learned a lot of useful reactions but unfortunately I didn't get to try many of them first hand (what's sad is I am a Chemistry major too). I've searched the internet back and ...
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Classes of Organometallic Compounds - Where do I put Grignard Reagents?
[Note- I've already seen this question Why do Magnesium and Lithium form *covalent* organometallic compounds? as user Mithoron was kind enough to point out, but the problem that I face is different ...
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Will Sodium Amide react with Epoxides in the same manner as Grignard Reagents?
I have been unable to find the reaction anywhere on the internet so I'm assuming the answer is no, although I would like an explanation as to why. I can't seem to find any reason why it would not ...
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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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Why is BuLi a better nucleophile than base?
In Carey, Sundberg Advanced Organic Chemistry it is written:
The relative slowness of the abstraction of protons from carbon acids by organolithium
reagents is probably also due to the compact ...
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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 the protons in pentacarbonylmethylmanganese show up at –0.21 ppm?
The $\ce{^1H}$ NMR of $\ce{Mn(CO)5CH3}$ shows a resonance at –0.21 ppm, which has to be due to the methyl group. Why are the protons so shielded?
I would have thought that all the pi backdonation ...
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Selectivity in Suzuki coupling of 2,4-dichloropyrimidine
I've seen many papers (see e.g. Synthesis 2010, 16, 2721–2724) in which the 4-chloro group of 2,4-dichloropyrimidine is selectively reacted under Suzuki coupling conditions. Is there any way where ...
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Role of Cu in Corey-House synthesis
What does $\ce{Cu}$ do? And why do we need it? Can we not do $\mathrm{S_N}2$ without it? And is there any other metal that can help in this? Maybe something like $\ce{Ag}$? I'm guessing this because ...
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