Beiträge zur Chemie des Bors, 199 Reaktionen eines Amino‐imino‐borans mit Anilin‐Derivaten und Carbonsäureamiden

Contributions to the Chemistry of Boron, 199. ‐ Reactions of an Amino‐imino‐borane with Anilines and Carboxylic Acid Amides The addition of aniline derivatives to ( tert ‐butylimino)(2,2,6,6‐tetramethylpiperidino)borane ( 1 ) leading to the mixed triaminoboranes ArNH(Me 3 CNH)Btmp ( 2 ) (tmp = 2,2,6,6‐tetramethylpiperidino) is sterically controlled. Reactions of 1 with acetamide produces O,N ‐diborylated acetimidic acid 4 . On the other hand, N ‐methylacetamide adds 1 to yield the N ‐borylated N ‐methylacetamide 5a exclusively. In contrast, N ‐isopropyl‐ and N‐tert ‐butylacetamide form also the O ‐borated isomers ( 6b, c ). Their proportion increases with the steric requirements of the N ‐substituent of the acetamide derivative.