通过使用[Mn(2,6-Cl 2 TPP)Cl](1)作为催化剂,Oxone / H 2 O 2作为氧化剂,我们开发了一种有效的方法,用于无环烯丙基取代的烯烃的赤型选择性环氧化,包括烯丙醇,胺和酯。末端烯丙基烯烃可达到9:1的赤型选择性,这明显高于使用m -CPBA作为氧化剂所达到的选择性。此外,这种环氧化方法的合成效用在关键的抗HIV药物中间体的立体选择性合成和糖基的环氧化中得到了强调。
作者:Andrew L. Kocen、Maurice Brookhart、Olafs Daugulis
DOI:10.1039/c7cc04953f
日期:——
We report a method for palladium-catalysed chain-running isomerization of terminal and internal alkenes. Using an air-stable 2,9-dimethylphenanthroline-palladium catalyst in combination with NaBAr4 promoter, olefins are converted to the most stable double bond isomer at −30 to 20 °C. Silyl enol ethers are readily formed from silylated allylic alcohols. Fluorinated substituents are compatible with the
Diastereoselective epoxidation of allylically substituted alkenes using metalloporphyrin catalysts
申请人:Che Chi-Ming
公开号:US20050209470A1
公开(公告)日:2005-09-22
Diastereoselective epoxidation of allylically substituted alkenes using metalloporphyrins as catalyst provides high trans-selectivities (i.e., trans-:cis-epoxide ratio). A diversity of cycloalkenes bearing different allylic substituents are shown to be efficiently epoxidized to afford the corresponding trans-epoxides with excellent trans-selectivities (up to >98%) and good yields (up to 99%). Acyclic allylic alkenes bearing different allylic substituents are efficiently epoxidized to afford the corresponding erythro-epoxides with good erythro-selectivities. The metalloporphyrin-catalyzed reactions exhibit up to 20 times higher trans-selectivities than the conventional method using m-chloroperoxybenzoic acid as oxidant.
Regio- and Stereospecific Formation of Protected Allylic Alcohols via Zirconium-Mediated S<sub>N</sub>2‘ Substitution of Allylic Chlorides
作者:Richard J. Fox、Gojko Lalic、Robert G. Bergman
DOI:10.1021/ja075967i
日期:2007.11.1
regio- and stereospecific SN2‘ substitution reaction between a zirconium oxo complex and allylicchloride has been achieved. The resulting allylic alcohol or TBS-protected allylic ether products were isolated in good to excellent yields with a wide range of E-allylic chlorides. A mechanism for the SN2‘ allylic substitution consistent with kinetic, stereochemical, and secondary isotope effect studies
Metalloporphyrin-Catalyzed Diastereoselective Epoxidation of Allyl-Substituted Alkenes
作者:Wing-Kei Chan、Man-Kin Wong、Chi-Ming Che
DOI:10.1021/jo047733c
日期:2005.5.1
developed an efficient method for erythro-selective epoxidation of acyclic allyl-substituted alkenes, including allylic alcohols, amines, and esters. Up to 9:1 erythro selectivities for terminal allyllic alkenes could be achieved, which are significantly higher than that achieved using m-CPBA as an oxidant. In addition, the synthetic utilities of this epoxidation method were highlighted in stereoselective synthesis
通过使用[Mn(2,6-Cl 2 TPP)Cl](1)作为催化剂,Oxone / H 2 O 2作为氧化剂,我们开发了一种有效的方法,用于无环烯丙基取代的烯烃的赤型选择性环氧化,包括烯丙醇,胺和酯。末端烯丙基烯烃可达到9:1的赤型选择性,这明显高于使用m -CPBA作为氧化剂所达到的选择性。此外,这种环氧化方法的合成效用在关键的抗HIV药物中间体的立体选择性合成和糖基的环氧化中得到了强调。
Isomerization of allylic silyl ethers catalyzed by ReO3(OSiR3) complexes
作者:Stéphane Bellemin-Laponnaz、Jean Pierre Le Ny、John A Osborn
DOI:10.1016/s0040-4039(99)02352-7
日期:2000.3
Efficient isomerization of allylic alcohols and allylic ethers at room temperature by rhenium (VII) oxo complexes is described.