Photolysis of the thiohydroximate ester derivative 21 of 2-carboethoxy-2-(2- (benzylseleno)pyridin-3-yl)tridecylcarboxylic acid (20) affords 2-dodecyl-2- carboethoxy-2,3-dihydroselenolo[2,3-b]pyridine (22) in 89% yield in a process presumably involving intramolecular homolytic substitution by a tertiary alkyl radical at selenium with loss of a benzyl radical. Work toward extending this methodology to the preparation of pyridine-fused selenium analogues of antioxidants is described.
Preparation of 2,3-dihydroselenolo[2,3-b]pyridines and related compounds by free-radical means
作者:Tahli Fenner、Jonathan M. White、Carl H. Schiesser
DOI:10.1039/b515385a
日期:——
3-dihydroselenolo[2,3-b]pyridine (22) in 89% yield in a process presumably involving intramolecular homolytic substitution by a tertiary alkyl radical at selenium with loss of a benzyl radical. Alternatively, rearrangement of O-(omega-haloalkyl)esters 34 of 2-carboethoxy-N-hydroxypyridine-2-selone affords azonianaphthalenium halides 37 in 79% yield.