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

Ruthenium porphyrins [Ru(F-20-TPP)(CO)] (F-20-TPP = 5,10,15,20-tetrakis(pentafluorophenyl)porphyrinato dianion) and [Ru(Por*)(CO)] (Por* = 5,10,15,20-tetrakis[(1S,4R,5R,8S)-1,2,3,4,5,6,7,8octahydro-1,4,5,8-dimethanoanthracen-9-yl]porphyrinato dianion) catalyzed intramolecular amidation of sulfamate esters p-X-C6H4(CH2)(2)OSO2NH2 (X = Cl, Me, MeO), XC6H4(CH2)(3)OSO2NH2 (X =p-F,p-MeO, m-MeO), and Ar(CH2)(2)OSO2NH2 (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(F-20-TPP)(CO)] with PhI=NSO2OCH2CCl3 (prepared by treating the sulfamate ester Cl3CCH2OSO2NH2 with PhI(OAc)(2)) afforded a bis(imido)ruthenium(VI) porphyrin, [Ru-VI(F-20-TPP)(NSO2OCH2CCl3)(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(F-20-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).