Domino Alkene-Isomerization–Claisen Rearrangement Strategy to Substituted Allylsilanes
摘要:
A one-pot isomerization Claisen protocol has been developed for the synthesis of highly substituted allylsilanes. Monosilylated divinyl ethers can be isomerized using a cationic iridium(I) catalyst followed by a thermal Claisen rearrangement to provide the allylsilanes in excellent yields and diastereoselectivities.
Exploring the reactivity of alkenes bearing silicon and/or tin in the hydroxyl-directed hydrogenation. A diastereoselective synthesis of heterobimetallic compounds
摘要:
The hydroxyl-directed hydrogenation of (E)- and (Z)-gamma-hydroxy vinylstannanes and silanes has been studied in the presence of (dppb)Rh(NBD)BF4 (1). Efficient routes to gamma-hydroxy stannanes and silanes have been developed. Diastereoselectivities from 60 to >500:1 were observed. A significant difference in reaction rate and pathway was observed between the (E)- and (Z)-vinylstannanes. We observed a reductive destannation process for the (Z)-stannanes which was influenced by the size of the R group. Competition studies were carried out to determine if steric or electronic effects were responsible for the reactivity patterns observed.
Platinum catalysed hydrosilylation of propargylic alcohols
作者:Catherine A. McAdam、Mark G. McLaughlin、Adam J. S. Johnston、Jun Chen、Magnus W. Walter、Matthew J. Cook
DOI:10.1039/c3ob40496j
日期:——
A facile and user-friendly protocol has been developed for the selective synthesis of E-vinyl silanes derived from propargylicalcohols using a PtCl2/XPhos catalyst system. The reaction is generally high yielding and provides a single regioisomer at the β-position with E-alkene geometry. The reaction is extremely tolerant of functionality and has a wide scope of reactivity both in terms of alkynes
PtCl2/XPhos: A highly efficient and readily available catalyst for the hydrosilylation of propargylic alcohols
作者:Mark G. McLaughlin、Matthew J. Cook
DOI:10.1039/c1cc14433b
日期:——
A highly regioselectivehydrosilylation of propargylicalcohols has been developed using an in situ prepared PtCl(2)/XPhos catalyst system. The reaction is tolerant of many functional groups and exhibits excellent regio and geometric selectivity.
Base-Mediated Cascade Rearrangements of Aryl-Substituted Diallyl Ethers
作者:Jolene P. Reid、Catherine A. McAdam、Adam J. S. Johnston、Matthew N. Grayson、Jonathan M. Goodman、Matthew J. Cook
DOI:10.1021/jo502403n
日期:2015.2.6
Two base-mediated cascade rearrangement reactions of diallyl ethers were developed leading to selective [2,3]-Wittig–oxy-Cope and isomerization–Claisen rearrangements. Both diaryl and arylsilyl-substituted 1,3-substituted propenyl substrates were examined, and each exhibits unique reactivity and different reaction pathways. Detailed mechanistic and computational analysis was conducted, which demonstrated