Questions tagged [organotransition-metal-chemistry]
For questions about the use of transition metals in organic synthesis.
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What is less coordinating to metals? Triflates or hexafluorophosphates, and why?
I saw a reaction where $\ce{AgOTf}$ and $\ce{AgPF6}$ were used, but I am trying to discern the reactivity between the two silver salts. I read that triflates and hexafluorophosphates are both non-...
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D-d splitting in transition metal ions
Cu+2 ion has total of 9 electrons in its 3d orbital. When it undergoes d-d splitting an electronic transition can take place between t2 and e as in {Cu(CN)4}-2 complex because of the presence of one ...
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Why is the silver salt ammoniated to form the Tollen's reagent? [duplicate]
When doing a distinguishing test between aldehydes and ketones using Tollen's reagent, is it necessary to convert $\ce{Ag+}$ ions into $\ce{Ag(NH3)2+}$ in order to oxidize the aldehyde?
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Why is the Suzuki coupling done under inert atmosphere?
There are plenty of sources saying that the Suzuki coupling is air-sensitive (even though there are some versions that require oxygen). However I'd like to know why a typical Suzuki coupling is air-...
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2
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Chemoselectively dihydroxylate a terminal alkene in the presence of an internal alkene?
The goal is to dihydroxylate the exo alkene, and then convert to a ketone.
Any suggestions would be apprecitated to either chemoselectively convert the terminal alkene, or directly convert the ...
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7
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1
answer
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Enantioselectivity of Noyori Asymmetric Hydrogenation
I'm unable to understand the enantioselectivity of Noyori's hydrogenation reaction, and would appreciate any help with the same:
Here's a mechanism I found on Wikipedia:
but, to my disappointment, ...
- 3,862
11
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2
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Why is Ni[(PPh₃)₂Cl₂] tetrahedral?
Since PPh₃ is strong field ligand and, the famous Wilkinson's catalyst, which also possess this ligand is square planar, then what makes the above complex tetrahedral?
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How does the bite angle of a ligand affect the efficiency of its catalyst?
I know that optimising the bite angle of a diphosphine ligand to its metal increases catalytic efficiency, and for cross-coupling reactions larger bite angles are favoured, but how does this have an ...
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How do the electronic properties of a catalyst affect the rate of oxidative addition?
In my project I have a coupling that was planned to be done using Pd (Suzuki or Stille possibly).
Initially, I used an aryl chloride (the SM had already the chloride so I went with it), but the ...
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What are the byproducts in a Suzuki reaction?
I am looking precisely at a coupling of a trifluoroborate with an aryl bromide. I know the mechanism of the Suzuki reaction, yet I cannot find any mention of the side products or degradation products ...
- 306
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Mechanism for palladium-catalysed spirocyclisation of conjugated diene
I'm trying to work out the catalytic cycle for the following process:
I gather that the palladium will be reduced from Pd(II) to Pd(0) in the process and that the 1,4-benzoquinone is a redoxidant. ...
- 131
20
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answer
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Carbometalation of alkenes
Alkynes are capable of undergoing carbometalation, e.g. with organocopper reagents:
Why don't the corresponding alkenes undergo analogous carbometalation reactions? Is β-elimination the issue?
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6
votes
1
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Selective transfer of least/most stable anion from organometallic reagents
When heterocuprate reagents participate in conjugate addition, the least stable anion is transferred from copper to the electrophile:
On the other hand, palladium-catalysed cross-coupling reactions ...
- 14.4k
4
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Ene-yne metathesis product
In the ene-yne metathesis how to know which product will form predominately, as the mechanisms to both are plausible?
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