Disproportionation of a ruthenium(III) nitro complex of a macrocyclic tertiary amine in an aqueous medium

Abstract

The reaction of trans-[RuLCI,] + (L = 1,5,9,13-tetramethyI-l ,5,9,13-tetraazacyclohexadecane) with NO2-in water at 60 "C leads to the formation of trans-[RuL(O)CI]+ and tran~-[RuL(OH)(N0)]~+. The formation of the products can be rationalized by the disproportionation of trans-[RuL(CI) (NO,)] +. The structures of the products have been determined by X-ray crystallography: trans-[RuL(O)CI] CIO,, space group Pna2, (no. 33), a = 12.616(1), b = 15.421 (3), c = 11.292(3) A; Ru=O and Ru-CI 1.75(1) and 2.435(6) A; trans-[R~L(0H)(NO)J[C10,]~, space group Pbca (no. 61), a = 20.459(3), b = 29.16(1), c = 25.1 3(1) A; average Ru-OH and Ru-NO 1.906(9) and 1.74(1) A.

A Controlled NO-Releasing Compound: Synthesis, Molecular Structure, Spectroscopy, Electrochemistry, and Chemical Reactivity of R,R,S,S-trans-[RuCl(NO)(cyclam)]2+(1,4,8,11-tetraazacyclotetradecane)

“…In the most closely related macrocyclic structure, trans-[Ru(OH)(NO)L](ClO 4 ) 2 , where L ) 1,5,9,13tetramethyl-1,5,9,13-tetraazacyclohexadecane, the average Ru-NO and N-O bond lengths are 1.74(2) Å and 1.13(2) Å, respectively, and the average Ru-N-O bond angle is 176(3)°. 34 The average Ru-N cyclam bond length of 2.092(4) Å (Table 2) is similar to 2.14(4) Å in R,S,R,R-trans-[Ru II (N 3 )(CH 3 N)(1,4,8,-11-tetramethyl-14ane)] + , 37 in which the steric bulk of the methyl groups results in a "three-up and one-down" configuration, and 2.083(3) Å in R,R,S,S-trans-[Ru III Cl 2 (cyclam)]Br, and 2.098 Å in R,R,S,S-trans-[RuCl(4-acpy)(cyclam)](BF 4 ), 38 in which the cyclam adopts the same configuration as reported here.…”

Synthesis of a nitro complex of RuIII(salen): Unexpected aromatic ring nitration by a nitrite salt

“…Characterization of a Ru(III)-nitro complex would be noteworthy because such species are generally unstable and undergo disproportionation to the (nitrosyl)ruthenium(II) and (nitrato)ruthenium(III) complexes [23][24][25][26][27]. Thus, there have been few reported examples of nitro ruthenium(III) complexes, and these did not include structural data [28][29][30].…”

A Synthetic Oxygen Atom Transfer Photocycle from a Diruthenium Oxyanion Complex

“…8 Furthermore, Suslick 9 and Vogler 10 have reported formation and reactivity of metal oxo species by photolytic cleavage of complexes with O-coordinated oxyanions, while Newcomb 11 and Bakac 12 have used flash photolysis to observe similar, highly reactive species. A major difficulty hindering the synthetic utility of this approach is the question of how to regenerate the M–OEO x precursor (Scheme 2).…”

“…Important precedents for this work include the elimination of nitrite ion from an ORuONO 2 complex to produce a dioxo Ru species and disproportionation of nitrite to form both RuO and RuNO complexes . Furthermore, Suslick and Vogler have reported formation and reactivity of metal oxo species by photolytic cleavage of complexes with O-coordinated oxyanions, while Newcomb and Bakac have used flash photolysis to observe similar, highly reactive species.…”