Metal-Free -C(sp(3))-H Functionalized Oxidative Cyclization of Tertiary N,N-Diarylamino Alcohols: Construction of N,N-Diarylaminotetrahydropyran Scaffolds

Abstract

Herein, we report an efficient synthetic method for the preparation of anomeric N,N-diarylaminotetrahydropyran scaffolds. The free radical 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO)/hypervalent iodine(III)- or TEMPO/I-2-mediated oxidative cyclization of tertiary amino alcohols was used to construct N,N-diarylaminotetrahydropyrans through -C(sp(3))-O bond formation, with the loss of only two Hatoms. This efficient synthetic method broadens the scope of viable -C(sp(3))-H functionalized amines to include conformational-bias-free substrates.