A catalytic amount of RuCl3 in the presence of excess of N-methyl-morpholine N-oxide (NMO) in DMF oxidizes secondary alcohols to ketones. Spectral studies reveal the formation of a Ru(V)-oxo species which is formed in situ on adding N-oxide. The formation of Ru(V) has been established by cyclic voltammetric studies. The mechanism involves the formation of Ru(V)-oxo species in steady state concentrations from Ru(III) and NMO, and this in turn reacts with the substrate in the rate-determining step. © 1987.

K. Vijayasri

Jayaraman Rajaram

Joseph C. Kuriacose

catalysis

CATALYSTS - RUTHENIUM COMPOUNDS

Oxides

N-METHYLMORPHOLINE N-OXIDE (NMO)

RUTHENIUM(III)-CATALYZED OXIDATION

SECONDARY ALCOHOLS

alcohols

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Ruthenium(III)-catalysed oxidation of secondary alcohols by N-methylmorpholine N-oxide (NMO)

Journal of Molecular Catalysis

N-methylmorpholine N-oxide (NMO) in conjunction with catalytic amounts of RuCl3 oxidizes unsaturated alcohols and primary alcohols selectively to the corresponding aldehydes. Kinetic studies indicate that the order with respect to NMO and catalyst is one. The order with respect to the substrate is variable, being zero at high concentrations and fractional at low concentrations. The proposed mechanism involves the rate-determining formation of an adduct between the alcohol and Ru(V). The activation parameters, determined under zero-order conditions with respect to the substrate, pertain to the formation of RuVO species from RuCl3 and NMO. © 1990.

Selective oxidation of unsaturated alcohols and primary alcohols by RuCl3/lv-methylmorpholine n-oxide (NMO) system: a kinetic study

The selective oxidation of thioethers to sulphoxides and of PPh3 to PPh3O can be effected by NMO in DMF as solvent in the presence of Ru(III) chloride as catalyst. Kinetic investigations indicate that the orders with respect to the catalyst and oxidant are one each. The order with respect to the substrate is variable being fractional order at low concentrations and zero at high concentrations. Spectrophotometric studies reveal the formation of a 1:1 complex between the substrate and the catalyst. A mechanism consistent with the above observations has been proposed and verified. © 1988 Indian Academy of Sciences.

Proceedings of the Indian Academy of Sciences - Chemical Sciences

Kinetics and mechanism of Ru(III)-catalysed oxidation of organic sulphides and triphenylphosphine by N-methylmorpholine N-oxide

Electronic, EPR and IR spectral evidence are given for the formation of the following active species: (1) ruthenium(VIII) in ruthenium(III)-PIA system, (2) ruthenium(V) oxo species in ruthenium(III)-N- oxide system, and (3) ruthenium(II)-phosphine oxide complex in ruthenium(II) N-oxide system. Cyclic voltammetric studies also suggest the formation of Ru(V) in ruthenium(III)-N-oxide system. © 1986.

Inorganica Chimica Acta

Spectral evidence for the formation of active intermediates from RuCl3 and RuCl2(PPh3)3 with N-methylmorpholine N-oxide (NMO) and phenyliodosoacetate (PIA) as mild oxidants

Catalytic amounts of RuCl2(PPh3)3 in the presence of excess of N-methylmorpholine N-oxide (NMO) in DMF, oxidizes secondary alcohols to ketones. Spectral and electrochemical studies reveal the formation of an oxocomplex of Ru(IV), on adding excess of NMO. In the proposed mechanism, the Ru(IV)-oxo complex formed from Ru(II) and NMO, attacks the substrate in the rate determining step. © 1986 Indian Academy of Sciences.

Journal of Chemical Sciences

RuCl2(PPh3)3 catalyzed oxidation of secondary alcohols with N-methylmorpholine N-oxide

Journal of the Chemical Society, Chemical Communications

Novel ruthenium(V) dioxo complexes: synthesis, characterization, and reactivity of trans-[Ru V (tmc)(O)2]ClO4(tmc = 1,4,8,11-tetramethyl-1,4,8,11-tetra-azacyclotetradecane)

Canadian Journal of Chemistry

The oxidation of alcohols by sodium ruthenate

Journal of Organometallic Chemistry

Ruthenium-catalyzed oxidation of alcohols and catechols using t-butyl hydroperoxide

Journal of the American Chemical Society

Ferricyanide oxidation of dihydropyridines and analogs

Tetrahedron Letters

Catalyzed oxidation of alcohols and aldehydes with iodosylbenzene

Journal	Journal of Molecular Catalysis
ISSN	03045102
Open Access	No