New fluoride ion-catalyzed reaction of -alkylacetylenes with silyl enol ethers. An efficient route to -alkyl-substituted propargylic alcohols and α-hydroxy ketones
Treatment of -alkylacetylenes, generated from 1--1- alkenephosphonates, with silyl enol ethers in the presence of a catalytic amount of tetrabutylammonium fluoride gives good yields of -alkyl-substituted propargyl alcohols or 4-(1--alkylidene)-1,3-dioxolane derivatives, the latter being converted to tie corresponding α-hydroxy ketones.
A General Synthesis of<i>S</i>-(β-Oxoalkyl)<i>O,O</i>-Dialkyl Thio- and Dithiophosphates
作者:P. Dybowski、A. Skowrońska
DOI:10.1055/s-1990-26957
日期:——
A novel, general synthesis of S-(β-oxoalkyl) and S-(β-oxocycloalkyl) O,O-dialkyl thio- and dithiophosphates based on the reaction of silyl enol ethers with O,O-dialkyl chlorothio- and O,O-dialkyl bromodithiophosphonates is described.
A general synthesis of a new class of compounds Se-(β-oxoalkyl) O,O-dialkyl selenophosphates based on selenophosphorylation of silyl enol ethers with the chloroselenotrialkoxyphosphonium chlorosulfide 3 is described.
Three-Component Coupling Approach to Trachyspic Acid
作者:Daniel C. Schmitt、Leighann Lam、Jeffrey S. Johnson
DOI:10.1021/ol202002r
日期:2011.10.7
Three-component coupling of the lithium enolate of t-BuOAc, silyl glyoxylate, and an alpha,beta-unsaturated ketone enables the rapid construction of the trachyspic acid carbon skeleton. A 3,4-disubstituted isoxazole is utilized to mask the C7/C9 dicarbonyl. New enolsilane/nitrile-oxide cycloadditions enable the preparation of various 3,4-disubstituted isoxazoles that are challenging to access by other means.