Tandem silylformylation–allyl(crotyl)silylation: a new approach to polyketide synthesis
摘要:
Tandem intramolecular silylformylation-allyl(crotyl)silylation reactions have been developed that allow the highly efficient synthesis of polyketide fragments. The substrates are subjected to Rh(I)-catalyzed silylformylation to afford beta-(diallyl)silyl aldehydes which undergo spontaneous uncatalyzed allylsilylation. This unusual spontaneous allylsilylation reaction is driven by strain release Lewis acidity, which arises from the similar to95degrees O-Si-C bond angle in the oxasilacyclopentane product of the silylformylation reaction. The methodology has been developed both for alkene and alkyne substrates, may be used to establish as many as three stereocenters, and has been shown to be amenable to use in an iterative fashion. (C) 2003 Elsevier Ltd. All rights reserved.
Tandem silylformylation–allyl(crotyl)silylation: a new approach to polyketide synthesis
摘要:
Tandem intramolecular silylformylation-allyl(crotyl)silylation reactions have been developed that allow the highly efficient synthesis of polyketide fragments. The substrates are subjected to Rh(I)-catalyzed silylformylation to afford beta-(diallyl)silyl aldehydes which undergo spontaneous uncatalyzed allylsilylation. This unusual spontaneous allylsilylation reaction is driven by strain release Lewis acidity, which arises from the similar to95degrees O-Si-C bond angle in the oxasilacyclopentane product of the silylformylation reaction. The methodology has been developed both for alkene and alkyne substrates, may be used to establish as many as three stereocenters, and has been shown to be amenable to use in an iterative fashion. (C) 2003 Elsevier Ltd. All rights reserved.
Tandem Intramolecular Silylformylation−Crotylsilylation: Highly Efficient Synthesis of Polyketide Fragments
作者:Michael J. Zacuto、Steven J. O'Malle、James L. Leighton
DOI:10.1021/ja026511y
日期:2002.7.1
Polyketide fragments may be rapidly and efficiently assembled in the tandem intramolecular silylformylation-crotylsilylation of alkenes and alkynes. The reactions establish up to three new stereocenters with good-to-excellent diastereoselectivity, and the use of the reaction in an iterative sense is demonstrated. In addition, a new dihydrosilane alcoholysis reaction has been developed, leading to a highly efficient sequence.
Tandem silylformylation–allyl(crotyl)silylation: a new approach to polyketide synthesis
作者:Michael J. Zacuto、Steven J. O'Malley、James L. Leighton
DOI:10.1016/j.tet.2003.04.004
日期:2003.11
Tandem intramolecular silylformylation-allyl(crotyl)silylation reactions have been developed that allow the highly efficient synthesis of polyketide fragments. The substrates are subjected to Rh(I)-catalyzed silylformylation to afford beta-(diallyl)silyl aldehydes which undergo spontaneous uncatalyzed allylsilylation. This unusual spontaneous allylsilylation reaction is driven by strain release Lewis acidity, which arises from the similar to95degrees O-Si-C bond angle in the oxasilacyclopentane product of the silylformylation reaction. The methodology has been developed both for alkene and alkyne substrates, may be used to establish as many as three stereocenters, and has been shown to be amenable to use in an iterative fashion. (C) 2003 Elsevier Ltd. All rights reserved.