A Facile Stereoselective Synthesis of (<i>Z</i>,<i>E</i>)-2-Silyl-Substituted 1,3-Dienes via Palladium-Catalyzed Cross-Coupling Reaction
作者:Ming-Zhong Cai、Xing-Lin Ye、Ping-Ping Wang
DOI:10.1055/s-2005-872174
日期:——
(E)-α-Halovinylsilanes undergo palludium-catalyzed cross-coupling reactions with (E)-alkenylzirconium complexes to afford stereoselectively (Z,E)-2-silyl-substituted 1,3-dienes in good yields.
Diastereoselective addition of lower order vinylcuprates to (R)-2,3-O-Isopropylideneglyceraldehyde
作者:Peter Metz、Andreas Schoop
DOI:10.1016/s0040-4020(01)81551-9
日期:1993.1
Highly syn or anti selective addition of lower order lithium vinylcuprates generated from alkenyl bromides 1 to (R)-2,3-O-isopropylideneglyceraldehyde (2) can be achieved, respectively, depending on the substitution pattern of the vinyl moiety and the solvent. Alpha-Trimethylsilyl substituted vinylcuprates possessing an alkyl substituent Z to copper react with excellent syn selectivity in ether whereas a highly anti selective addition is observed for cuprates bearing a hydrogen atom Z or alpha to the metal in THF. A model is proposed to rationalize these complementary selectivities.
Facile 1,3-hydride transfer in a cycloheptyl cation
作者:Steven R. Angle、Heather L. Mattson-Arnaiz
DOI:10.1021/ja00051a009
日期:1992.12
The intramolecular addition of a benzylic cation to a vinylsilane was studied. The benzylic (methoxyethoxy)methyl ether 1 was shown to undergo an unusual cyclization to afford a substituted cycloheptene (12) upon treatment with a Lewis acid. Following cyclization, the molecule undergoes a formal 1,3-hydride shift, followed by elimination to give styrene 12.