The induction period observed in the cis‐RuCl2(DMSO)4 catalyzed oxidation of thioethers (S) to sulfoxides by N‐methylmorpholine N‐oxide (NMO) is attributed to the rate of formation of the active species viz. RuCl2(DMSO)3S. Cyclic voltammetric studies indicate formation of the RuIV = 0 species. Based on the variable orders in NMO and first order in each of the other reactants, a mechanism is proposed where the active species generated in situ reacts with NMO in a slow step to form RuIV oxo complex which then decomposes to give the product. Copyright © 1990 John Wiley &amp; Sons, Inc.

Jayaraman Rajaram

Joseph C. Kuriacose

CATALYSTS - RUTHENIUM COMPLEX

CHEMICAL REACTIONS - Reaction Kinetics

SULFUR COMPOUNDS - OXIDATION

Cyclic voltammetry

METHYLMORPHOLINE OXIDE

reaction mechanism

SULFIDE OXIDATION

SULFOXIDES

THIOETHERS

Ethers

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

International Journal of Chemical Kinetics

Oxidation of dibutylsulfide, diphenylsulfide, methylphenylsulfide and dibenzylsulfide to the corresponding sulfoxides by N-methylmorpholine N-oxide (NMO) catalyzed by RuCl2(PPh3)3 in DMF solvent is reported. The reaction is first order in both catalyst and N-oxide. The order with respect to the substrate is variable, being zero at higher concentrations and fractional at lower concentrations. The order of reactivity observed for the substrates is as follows: dibutylsulfide ≈ dibenzylsulfide &gt; methylphenylsulfide &gt; diphenylsulfide. RuCl2(PPh3)3 oxidizes olefins to form epoxides at a slower rate. The order of reactivity observed for the two types of substrates parallels their nucleophilicity (sulfides &gt; alkenes). Spectral studies indicate 1:1 complex formation between RuCl2(PPh3)3 and the sulfides. The active oxidant is the Ru(IV)oxo complex formed by the oxidation of Ru(II) by NMO. © 1989.

Journal of Molecular Catalysis

Kinetics and mechanism of RuCl2PPh3)3-catalyzed oxidation of sulfides 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

ChemInform

ChemInform Abstract: cis- and trans-Dihalotetrakis(dimethyl sulfoxide)ruthenium(II) Complexes (RuX2(DMSO)4; X: Cl, Br): Synthesis, Structure, and Antitumor Activity.

Inorganic Chemistry

Masthead

Cis- and trans-dioxo complexes of chlororuthenium(VI)

cis‐RuCl2(DMSO)4‐catalyzed oxidation of sulfides by N‐methylmorpholine N‐oxide (NMO)

Journal	International Journal of Chemical Kinetics
ISSN	05388066
Open Access	No