Abstract
Two synthetic methods leading to the new n , n '-diphosphonylketones 2 and 2 ' are reported. The first method involves the base-catalyzed addition of diethylphosphite to diarylideneketones. The second one utilizes the reaction of triethylphosphite and ethoxydiphenylphosphine with g , g '-bis(dimethylamino)ketone hydrochlorides. On reaction with phenylhydrazine hydrochloride, compounds 2 and 2 ' give the corresponding 2-(phosphonoethyl)3-(phosphonomethyl)indoles 3 . The structure of all obtained products is confirmed by NMR ( 1 H, 31 P, 13 C) and IR spectroscopy.