An innovative protocol for the synthesis of 3-(pyridin-2-yl)-5-sec- aminobiphenyl-4-carbonitriles and 9,10-dihydro-3-(pyridine-2-yl)-1-secQ- aminophenanthrene-2-carbonitriles

摘要

Herein, we present an innovative, novel, and highly convenient protocol for the synthesis of 3-(pyridin-2-yl)-5-sec-aminobiphenyl-4-carbonitriles (6a, 6b, 6c, 6d, 6e, 6f, 6g) and 9,10-dihydro-3-(pyridine-2-yl)-1-sec-aminophenanthrene- 2-carbonitriles (10a, 10b, 10c, 10d, 10e), which have been delineated from the reaction of 4-sec-amino-2-oxo-6-aryl-2H-pyran-3-carbonitrile (4a, 4b, 4c, 4d, 4e, 4f, 4g) and 4-sec-amino-2-oxo-5,6-dihydro-2H-benzo[h]chromene-3- carbonitriles (9a, 9b, 9c, 9d, 9e) with 2-acetylpyridine (5) through the ring transformation reaction by using KOH/DMF system at RT. The salient feature of this procedure is to provide a transition metal-free route for the synthesis of asymmetrical 1,3-teraryls like 3-(pyridin-2-yl)-5-sec-aminobiphenyl-4- carbonitriles (6a, 6b, 6c, 6d, 6e, 6f, 6g) and 9,10-dihydro-3-(pyridine-2-yl)-1- sec-aminophenanthrene-2-carbonitriles (10a, 10b, 10c, 10d, 10e). The novelty of the reaction lies in the creation of an aromatic ring from 2H-pyran-2-ones and 2H-benzo[h]chromene-3-carbonitriles via two-carbon insertion from 2-acetylpyridine (5) used as a source of carbanion.