Intramolecular C-N bond formation reactions catalyzed by ruthenium porphyrins: Amidation of sulfamate esters and aziridination of unsaturated sulfonamides

Abstract

Ruthenium porphyrins [Ru(F20-TPP)(CO)] (F20-TPP = 5,10,15,20-tetrakis(pentafluorophenyl)porphyrinato dianion) and [Ru(Por*)(CO)] (Por* = 5,10,15,20-tetrakis[(1S,4R,5R,8S)-1,2,3,4,5,6,7,8-octahydro-1,4:5, 8-dimethanoanthracen-9-yl]porphyrinato dianion) catalyzed intramolecular amidation of sulfamate esters p-X-C6H4(CH 2)2OSO2NH2 (X = Cl, Me, MeO), XC6H4(CH2)3OSO2NH 2 (X = p-F, p-MeO, m-MeO), and Ar(CH2)2OSO 2NH2 (Ar = naphthalen-1-yl, naphthalen-2-yl) with PhI(OAc)2 to afford the corresponding cyclic sulfamidates in up to 89% yield with up to 100% substrate conversion; up to 88% ee was attained in the asymmetric intramolecular amidation catalyzed by [Ru(Por*)(CO)]. Reaction of [Ru(F20-TPP)(CO)] with PhI=NSO2OCH 2CCl3 (prepared by treating the sulfamate ester Cl 3CCH2OSO2NH2 with PhI(OAc) 2) afforded a bis(imido)ruthenium(VI) porphyrin, [Ru VI(F20-TPP)(NSO2OCH2CCl 3)2], in 60% yield. A mechanism involving reactive imido ruthenium porphyrin intermediate was proposed for the ruthenium porphyrin-catalyzed intramolecular amidation of sulfamate esters. Complex [Ru(F20-TPP)(CO)] is an active catalyst for intramolecular aziridination of unsaturated sulfonamides with PhI(OAc)2, producing corresponding bicyclic aziridines in up to 87% yield with up to 100% substrate conversion and high turnover (up to 2014).