Highly diastereoselective Markovnikov hydration of 3,4-dialkoxy-1-alkenes and 4,5-dialkoxy-2-alkenes via a hydroboration-oxidation process
摘要:
Hydroboration-oxidation of 3,4-dialkoxy- and 3,4,5-trialkoxy-1-alkenes and 4,5-dialkoxy-2-alkenes occurs to give high proportions of the secondary alcohols (Markovnikov hydration) with excellent diastereoselectivity (anti to the allylic alkoxide). (C) 1999 Elsevier Science Ltd. All rights reserved.
Highly Stereoselective Semihydrogenation of Alkynes Promoted by Nickel(0) Nanoparticles
作者:Francisco Alonso、Iñaki Osante、Miguel Yus
DOI:10.1002/adsc.200505327
日期:2006.2
A new method for the highlystereoselective cis-semihydrogenation of internal alkynes is described based on in situ generated Ni(0) nanoparticles and molecular hydrogen. This reduction system also allows the semihydrogenation of terminal alkynes.
The Regio‐ and Stereospecific Intermolecular Dehydrative Alkoxylation of Allylic Alcohols Catalyzed by a Gold(I) N‐Heterocyclic Carbene Complex
作者:Paramita Mukherjee、Ross A. Widenhoefer
DOI:10.1002/chem.201203987
日期:2013.3.4
AgClO4 catalyzes the intermolecular dehydrative alkoxylation of primary and secondaryallylic alcohols with aliphatic primary and secondary alcohols to form allylic ethers. These transformations are regio‐ and stereospecific with preferential addition of the alcohol nucleophile at the γ‐position of the allylic alcohol syn to the departing hydroxyl group and with predominant formation of the E stereoisomer
Silylene oxonium ylides: di-tert-butylsilylene insertion into C–O bonds
作者:Laura E. Bourque、Pamela A. Haile、Janice M.N. Loy、K.A. Woerpel
DOI:10.1016/j.tet.2009.04.016
日期:2009.7
Allylic ethers undergo insertions of silylenes into C-O bonds to form allylic silanes. Silylene insertion into C-O acetal bonds was also observed. Formation of silylene ylide intermediates led to [ 1,2]-Stevens rearrangement products as well as [2,3]-sigmatropic products depending upon the steric environment of the starting allylic ether. (C) 2009 Elsevier Ltd. All rights reserved.