.ALPHA.,.ALPHA.-gem-Difluorination of .ALPHA.-(Alkylthio)acetophenone Derivatives with N-Fluoropyridinium Salts.
作者:Sunao TAKEDA、Yasushi KANEKO、Hiromichi ETO、Minoru TOKIZAWA、Susumu SATO、Kouiti YOSHIDA、Setsuo NAMIKI、Masaki OGAWA
DOI:10.1248/cpb.48.1097
日期:——
The α, α-gem-difluorination of 2', 4'-difluoro-α-(methylthio)acetophenone (1a) with N-fluoropyridinium salts gave 2', 4', α, α-tetrafluoro α-(methylthio)acetophenone (3a). This reaction was accelerated by the addition of zinc chloride, zinc bromide or anhydrous iron(III) chloride, and higher yields than the reaction without additives were obtained. The gem-difluorination reaction using FP-T300 in the presence of zinc bromide was applicable to other α-(alkylthio)acetophenone derivatives (1).
用 N-氟吡啶鎓盐对 2',4'-二氟-α-(甲硫基)苯乙酮 (1a) 进行α,α-锗二氟化反应,可得到 2',4',α,α-四氟-α-(甲硫基)苯乙酮 (3a)。加入氯化锌、溴化锌或无水氯化铁(III)可加速该反应,并获得比不加入添加剂时更高的产率。在溴化锌存在下使用 FP-T300 进行的宝石二氟化反应适用于其他 α-(烷硫基)苯乙酮衍生物 (1)。