Synthetic approaches towards 4-(silylmethyl)-2-azetidinones
摘要:
Differently substituted 4-(silylmethyl)-2-azetidinones were prepared starting form the corresponding 4-acetoxy-2-azetidinones with silylmethylmagnesium chlorides. The same kind of beta-lactams were synthesized ''via'' cycloaddition of allylsilanes and chlorosulfonyl isocyanate (CSI).
Thiophilic allylation of dithioesters and trithiocarbonates
作者:Antonella Capperucci、Alessandro Degl'Innocenti、M.Cristiana Ferrara、Bianca F. Bonini、Germana Mazzanti、Paolo Zani、Alfredo Ricci
DOI:10.1016/0040-4039(94)88190-1
日期:1994.1
Reaction of dithioesters and trithiocarbonates with silylated nucleophiles under fluoride ion conditions affords a novel example of silyl mediated regiochemical control in the thiophilic functionalization.
Acyclic stereoselection in the reaction of chiral allylsilanes with electrophiles
作者:Cristina Nativi、Giovanni Palio、Maurizio Taddei
DOI:10.1016/s0040-4039(00)74278-x
日期:1991.3
The presence of a stereocenter close to the double bond of an allylsilane has an influence on the stereochemistry of the reaction with electrophiles. The stereoselectivity follows the rule of electrophilic attack on a trigonal carbon adjacent to a stereogenic center proposed by Houk. From chiral allylsilanes and achiral aldehydes it is possible to prepare homo allyl alcohols with three stereocenters
An efficient synthesis of various protected syn-beta-sulfenyl amides is described. These are prepared from the corresponding enantiopure amino allylsilanes which are in turn obtained from naturally occurring amino acids. The key step for introduction of the sulfur substituent is a diastereoselective electrophilic sulfodesilylation which is carried out with phthalimidesulfenyl chloride. The resulting homochiral beta-phthalimidesulfenyl amines with an allylic sulforated stereogenic center are useful building blocks, as they represent a starting point for subsequent functional manipulations.