Palladium-Templated Regio- and Stereoselective Cyclization of 2'-Alkenyl 2-Alkynoates and Its Synthetic Applications
摘要:
2'-Alkenyl 2-alkynoates undergo facile stereoselective cyclization to alpha-(haloalkylidene)-gamma-butyrolactones upon treatment with a catalytic amount of palladium complex in the presence of CuX(2) and LiX. When an alkyl group is introduced to the 1'-position of the alkenyl group, unsubstituted 2-propynoates mainly give trans-beta, gamma-disubstituted gamma-lactones, and substituted 2-propynoates afford cis-beta,gamma-disubstituted gamma-lactones. Further elaborations of the halogen atoms and the synthesis of A-factor using this method are exemplified.
Palladium-Templated Regio- and Stereoselective Cyclization of 2'-Alkenyl 2-Alkynoates and Its Synthetic Applications
摘要:
2'-Alkenyl 2-alkynoates undergo facile stereoselective cyclization to alpha-(haloalkylidene)-gamma-butyrolactones upon treatment with a catalytic amount of palladium complex in the presence of CuX(2) and LiX. When an alkyl group is introduced to the 1'-position of the alkenyl group, unsubstituted 2-propynoates mainly give trans-beta, gamma-disubstituted gamma-lactones, and substituted 2-propynoates afford cis-beta,gamma-disubstituted gamma-lactones. Further elaborations of the halogen atoms and the synthesis of A-factor using this method are exemplified.
Selective ene-yne coupling-functionalization: A new strategy in constructing heterocycles
作者:Zhong Wang、Xiyan Lu
DOI:10.1016/0040-4020(95)00035-7
日期:1995.2
Fluorinated derivatives of 3-alkylidene-2(3H)-dihydrofuranone have been synthesized by sodium dithionite initiated tandem perfluoroalkylation-cyclization of allylic 2-alkynoates in fair to good yield and high stereoselectivity. Fluorinated 3-alkylidene-2(3H)-pyrrolidone derivatives were prepared similarly. A mechanistic rationale concerning the different radical steps and the differences between esters
Palladium catalyzed cyclization-carbonylation of allylic 2-alkynoates: Facile synthesis of α-alkylidene-γ-butyrolactone β-acetic acid derivatives
作者:Jianguo Ji、Xiyan Lu
DOI:10.1016/s0040-4020(01)85373-4
日期:1994.1
alpha-(Z)- and (E)- Chtoroalkylidene-gamma-butyrolactone beta-acetic acid derivatives were prepared from easily available acyclic allylic 2-alkynoates using Pd-2(dba)(3) CHCl3 as catalyst under 1 atm of CO in the presence of CuCl2 and LiCl in high stereoselectivity.
A convenient stereoselective synthesis of fluorinated α-alkylidene-γ-butyrolactone derivatives
作者:Xiyan Lu、Zhong Wang、Jianguo Ji
DOI:10.1016/s0040-4039(00)75852-7
日期:1994.1
Fluorinated alpha-alkylidene-gamma-butyrolactone derivatives were synthesized stereoselectively via a sodium dithionite initiated radical perfluoroalkylation-cyclization of acyclic allylic alkynoates in high yields under mild conditions.
Lu Xiyan, Wang Zhong, Ji Jianguo, Tetrahedron Lett, 35 (1994) N 4, S 613-616
作者:Lu Xiyan, Wang Zhong, Ji Jianguo
DOI:——
日期:——
Palladium-Templated Regio- and Stereoselective Cyclization of 2'-Alkenyl 2-Alkynoates and Its Synthetic Applications
作者:Jianguo Ji、Chunming Zhang、Xiyan Lu
DOI:10.1021/jo00110a018
日期:1995.3
2'-Alkenyl 2-alkynoates undergo facile stereoselective cyclization to alpha-(haloalkylidene)-gamma-butyrolactones upon treatment with a catalytic amount of palladium complex in the presence of CuX(2) and LiX. When an alkyl group is introduced to the 1'-position of the alkenyl group, unsubstituted 2-propynoates mainly give trans-beta, gamma-disubstituted gamma-lactones, and substituted 2-propynoates afford cis-beta,gamma-disubstituted gamma-lactones. Further elaborations of the halogen atoms and the synthesis of A-factor using this method are exemplified.