Ligand Controlled Ir-Catalyzed Regiodivergent Oxyamination of Unactivated Alkenes
作者:Honghui Lei、John H. Conway、Caleb C. Cook、Tomislav Rovis
DOI:10.1021/jacs.9b06366
日期:2019.7.31
An intramolecular Ir(III)-catalyzed regiodivergent oxyamination of unactivated alkenes provides valuable γ-lactams, γ-lactones and δ-lactams. The regioselectivity is controlled by the electronically tunable cyclopentadienyl Ir(III)-complexes enabling oxyamination via either 5-exo or 6-endo pathways. With respect to the mechanism, we propose a highly reactive [3.1.0] bicycle intermediate derived from
Reactions of organic halides with olefins under Ni o -catalysis. Formal addition of hydrocarbons to CC-double bonds
作者:Reiner Sustmann、Peter Hopp、Peter Holl
DOI:10.1016/s0040-4039(01)80283-5
日期:——
The reaction of various types of organic halides with electron deficient olefins under the influence of NiCl2 × 6 H2O in the presence of zinc and pyridine leads to formal addition products of hydrocarbons to CC-double bonds in good yield.
在锌和吡啶的存在下,各种类型的有机卤化物与缺电子的烯烃在NiCl 2 ×6 H 2 O的作用下反应,可将烃正式加成产物成CC-双键。
Palladium-Catalyzed Synthesis of 2,1‘-Disubstituted Tetrahydrofurans from γ-Hydroxy Internal Alkenes. Evidence for Alkene Insertion into a Pd−O Bond and Stereochemical Scrambling via β-Hydride Elimination
作者:Michael B. Hay、John P. Wolfe
DOI:10.1021/ja054754v
日期:2005.11.30
diastereoselectivity in reactions of acyclic internal alkene substrates likely derives from a series of reversible β-hydride elimination and σ-bond rotation processes that occur following a rare intramolecular alkene syn-insertion into an intermediate Pd(Ar)(OR) complex. In addition, these studies shed light on the chemoselectivity of insertion, suggesting that the alkene inserts into the Pd−O bond in preference
The conjugate addition of cis- or trans-1-alkenyl-cuprolithium complexes (RCHCH)2CuLi · Xn1 to α, β-unsaturated carbonyl compounds was found to occur with high retention of double bond geometry, affording isomerically pure cis- or trans-γ, δ-ethylenic carbonyl compounds. The same 1-alkenylcuprates also react stereospecifically with alkyl halides to give isomerically pure cis- or trans-olefins.
发现在α,β-不饱和羰基化合物上可以顺式或反式-1-烯基-铜锂复合物(RCHCH)2 CuLi·X n 1的共轭加成反应,可以保持双键几何结构的高度保留,从而提供异构体纯的顺式-或反式-γ,δ-烯属羰基化合物。相同的1-烯基铜酸酯也与卤代烷立体定向反应,得到异构纯的顺式或反式烯烃。
Catalytic Epoxidation of Alkenes with Oxone
作者:Scott E. Denmark、David C. Forbes、David S. Hays、Jeffrey S. DePue、Richard G. Wilde
DOI:10.1021/jo00110a049
日期:1995.3
A practical, general and efficient protocol for the catalytic epoxidation of alkenes has been developed. The in situ generation of reactive dioxiranes capable of epoxidizing a variety of alkenes under biphasic conditions has been accomplished using phase transfer catalysts bearing a carbonyl group. Optimal epoxidation conditions employ 10 mol % of 1-dodecyl-1-methyl-4-oxopiperidinium triflate (8d(+)OTf(-)) in a CH2Cl2/pH 7.5-8.0 biphase using potassium monoperoxosulfate (Oxone) as the oxidant. Optimization of the conditions identified (1) slow addition rate, (2) pH 7.5-8.0, (3) N-dodecyl chain, and (4) the triflate salt as key experimental and structural variables. A selection of nine olefins was successfully oxidized to the corresponding epoxides in 83-96% yield.