Novel ruthenium-catalyzed cleavage of allyl protecting group in lactams
摘要:
A convenient and general method of synthesis of NH-lactams via Grubbs' carbene promoted isomerization of the respective N-allyl lactams followed by RuCl3-catalyzed enamide cleavage has been developed. (C) 2003 Elsevier Ltd. All rights reserved.
A Practical Ruthenium-Catalyzed Cleavage of the Allyl Protecting Group in Amides, Lactams, Imides, and Congeners
作者:Benito Alcaide、Pedro Almendros、Jose M. Alonso
DOI:10.1002/chem.200501227
日期:2006.3.20
deprotection of N-allylic amide-like moieties was developed. The first examples accounting for the ruthenium-catalyzed deallylation of amides, lactams, imides, pyrazolidones, hydantoins, and oxazolidinones have been achieved by the sequential use of Grubbs carbene (isomerization step) and RuCl(3) (oxidation step). A variety of substrates, including enantiopure multifunctional beta- and gamma-lactams, can
Reaction of -silyl imines with silyi keteneacetals in the presence of ZnI2 and t-butyl alcohol, followed by treatment of the intermediate -silyl β-aminoesters with MeMgBr, produces -silyl-azetidin-2-ones in good yield; use of trimethylsilyl triflate as Lewis acid catalyst can be advantageous in some cases. The preparation of the -t-butyldimethylsilyl imine of ethyl glyoxylate in this context is detailed
Reaction of silyl ketene acetals with N-trimethylsilyl imines: a route to N-unsubstituted azetidin-2-ones
作者:Ernest W. Colvin、Daniel G. McGarry
DOI:10.1039/c39850000539
日期:——
Reaction of N-trimethylsilylimines with silylketeneacetals in the presence of ZnI2 and t-butyl alcohol, followed by treatment in situ of the intermediate N-silyl β-aminoesters with MeMgBr, leads to N-unsubstitutedazetidin-2-ones in good yield.
Novel ruthenium-catalyzed cleavage of allyl protecting group in lactams
作者:Benito Alcaide、Pedro Almendros、José M. Alonso
DOI:10.1016/j.tetlet.2003.09.165
日期:2003.11
A convenient and general method of synthesis of NH-lactams via Grubbs' carbene promoted isomerization of the respective N-allyl lactams followed by RuCl3-catalyzed enamide cleavage has been developed. (C) 2003 Elsevier Ltd. All rights reserved.