Synthesis of Three‐, Five‐, and Six‐Membered Heterocycles Derived from New β‐Amino‐α‐(trifluoromethyl) Alcohols

Abstract

AbstractNucleophilic trifluoromethylation of α‐imino ketones 2, derived from arylglyoxal, with Ruppert–Prakash reagent (CF3SiMe3) offers a convenient access to the corresponding O‐silylated β‐imino‐α‐(trifluoromethyl) alcohols. In a ‘one‐pot’ procedure, by treatment with NaBH4, these products smoothly undergo reduction and desilylation yielding the expected β‐amino‐α‐(trifluoromethyl) alcohols 4. The latter were used as starting materials for the synthesis of diverse trifluoromethylated heterocycles, including aziridines 5, 1,3‐oxazolidines 8, 1,3‐oxazolidin‐2‐ones 9, 1,3,2‐oxazaphospholidine 2‐oxides 10, 1,2,3‐oxathiazolidine 2‐oxides 11, and morpholine‐2,3‐diones 12. An optically active 5‐(trifluoromethyl)‐substituted 1,3‐oxazolidin‐2‐one 9g was also obtained.