Tuning the reactivity of dioxoruthenium(VI) porphyrins toward an arylimine by altering porphyrin substituants

Abstract

Reaction of dioxoruthenium(VI) porphyrins [RuVI(Por)O 2] with arylimine HN=CPh2 in dichloromethane afforded bis-(methyleneamido)ruthenium(IV) porphyrins [RuIV(Por)(N=CPh 2)2] for Por = 4-CI-TPP and TMP; (methyleneamido)- hydroxoruthenium(IV) porphyrins [RuVI(Por)(N=CPh2)(OH)] for Por = TPP and TIP; and bis(arylimine)ruthenium(II) porphyrins [Ru II(Por)(HN=CPh2)2] for Por = 3,5-Cl 2TPP and 3,5-(CF3)2TPP. In dichloromethane solution exposed to air, complex [RuII(3,5-Cl2TPP)(HN= CPh2)2] underwent oxidative deprotonation.to form [Ru IV(3,5-Cl2TPP)(N= CPh2)2]. The new ruthenium porphyrins were identified by 1H NMR, UV-vis, IR, and mass spectroscopy, along with elemental analysis. X-ray crystal structure determinations of [RuIV(4-Cl-TPP)(N=CPh2)2], [RuIV(TPP)(N=CPh2)-(OH)], and [RuII(3,5- (CF3)2TPP)(HN=CPh2)2] revealed the Ru-N(methyleneamido) or Ru-N(arylimine) distances of 1.897(5) Å (average), 1.808(4) Å, and 2.044(2) Å (average), respectively. © 2005 American Chemical Society.