Synthesis of gem -difluoromethylenated compounds employing α,α-difluoro-α-phenylsulfanyl-α-trimethylsilylmethane (PhSCF<inf>2</inf>SiMe<inf>3</inf>) as a gem -difluoromethylene building block

Abstract

© Georg Thieme Verlag Stuttgart. α,α-Difluoro-α-phenylsulfanyl-α-trimethylsilylmethane (PhSCF2SiMe3) is a synthetically important fluorinating reagent. This account summarizes our work on the synthetic utility of α,α-difluoro-α-phenylsulfanyl-α-trimethylsilylmethane as a versatile gem-difluoromethylene building block for the preparation of a variety of gem-difluoromethylenated compounds. 1 Introduction 2 Fluoride-Catalyzed Nucleophilic Addition of PhSCF2SiMe3 to Carbonyl Compounds 2.1 Synthesis of gem-Difluoromethyl Aryl Ketones 2.2 Synthesis of gem-1,1-Difluoroalkenes 2.3 Synthesis of gem-Difluoromethylenated Cyclopentanol Derivatives 3 Fluoride-Catalyzed Nucleophilic Addition of PhSCF2SiMe3 to N-Substituted Phthalimides and Succinimide Derivatives 3.1 Synthesis of gem-Difluoromethylenated 1-Azabicyclic Compounds 3.2 Asymmetric Synthesis of gem-Difluoromethylenated Pyrrolizidines and Indolizidines 4 Fluoride-Catalyzed Nucleophilic Addition of PhSCF2SiMe3 to Anhydride Derivatives 5 Fluoride-Catalyzed Chemoselective Nucleophilic Addition of PhSCF2SiMe3 to Keto Esters 5.1 Synthesis of gem-Difluoromethylenated Spiro-γ-butyrolactones 5.2 Synthesis of gem-Difluoromethylenated Bicyclo[m.n.0]-alkan-1-ols and Their Ring-Expansion into gem-Difluoromethylenated Macrocyclic Lactones 6 Asymmetric Synthesis of 3,3-Difluoro-2-propanoylbicyclo[3.3.0]octanes 7 Conclusions