Synthesis of β-Hydroxy-α,α-difluorosulfonamides from Carbanions of Difluoromethanesulfonamides
作者:Jacob Soley、Scott D. Taylor
DOI:10.1021/acs.joc.1c00378
日期:2021.5.7
The synthesis of β-hydroxy-α,α-difluorosulfonamides was achieved by reacting difluoromethanesulfonamides with KHMDS in the presence of an aldehyde or ketone. The reaction exhibited a dramatic counterion effect with KHMDS or NaHMDS usually giving excellent yields in minutes, while lithium bases gave little or no product. Excellent yields and high diastereomeric ratios were achieved with Nα-benzyl-Nα-phenylfluorenyl
β-羟基-α,α-二氟磺酰胺的合成是通过在醛或酮存在下使二氟甲磺酰胺与KHMDS反应来实现的。该反应对KHMDS或NaHMDS表现出显着的抗衡离子作用,通常可在数分钟内获得出色的收率,而锂碱则几乎没有或没有产物。优异的产率和非对映体高比率与实现Ñ α苄基Ñ α -phenylfluorenyl(PHF)保护的手性氨基醛衍生自氨基酸。脱保护后,β-羟基-α,α-磺酰胺在肽偶联和Mitsunobu条件下反应,以极好的总产率提供拟肽。