Metal‐Free α‐C(sp³)−H Functionalized Oxidative Cyclization of Tertiary N,N‐Diarylamino Alcohols: Construction of N,N‐Diarylaminotetrahydropyran Scaffolds

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 α‐C(sp 3 )−O bond formation, with the loss of only two H atoms. This efficient synthetic method broadens the scope of viable α‐C(sp 3 )−H functionalized amines to include conformational‐bias‐free substrates.