New methods and reagents in organic synthesis. 19. Synthesis and rearrangement of .ALPHA.-acylsulfonyldiazomethanes (.ALPHA.-diazo-.BETA.-ketosulfones).
作者:YINGCHE KUO、TOYOHIKO AOYAMA、TAKAYUKI SHIOIRI
DOI:10.1248/cpb.30.526
日期:——
Sulfonyldiazomethanes (1), as stable and safe substitutes for hazardous diazomethane, have been conveniently acylated with acyl chlorides in the presence of triethylamine in acetonitrile to give α-acylsulfonyldiazomethanes (α-diazo-β-ketosulfones, 3) in good yields. Investigation of their thermal behavior in the presence of benzyl alcohol has revealed that Wolff rearrangement occurs to give α-sulfonylacetates (4). The overall process may provide a new, safe method for the Arndt-Eistert synthesis of α-sulfonylacetates (4) from carboxylic acid chlorides.
arylsulfonyl radicals with diazo compounds is described for the synthesis of various arylsulfones under mild conditions. In this reaction, the cheap, environmentally friendly, and readily available inorganic K2S2O5 is employed as the sulfur dioxide source for providing arylsulfonyl radicals. In addition, a radical mechanism involving the insertion of sulfur dioxide with aryl radicals followed by the coupling
描述了一种新型铜催化的芳基磺酰基与重氮化合物的交叉偶联,用于在温和条件下合成各种芳基砜。在该反应中,使用廉价、环保且易于获得的无机 K 2 S 2 O 5作为二氧化硫源来提供芳基磺酰基自由基。此外,提出了一种自由基机理,包括将二氧化硫插入芳基自由基,然后将芳基磺酰基自由基与铜卡宾偶联。