Studies on transition metal nitrido and oxo complexes. Part 161. The nature of the oxoruthenates involved in some rutheniumcatalysed organic oxidations

Abstract

Electronic spectroscopy has been used to ascertain the nature of the oxoruthenates present in a number of organic oxidations catalysed by ruthenium complexes reported in the literature. The utility of oxoruthenates as catalysts with [Fe(CN)6] 3-as co-oxidant for the conversion of primary alcohols to carboxylic acids and secondary alcohols to ketones has been assessed.

Synthesis and Characterization of 3‐(Aryl azo)‐4‐hydroxy‐1,2‐naphthoquinone Ruthenium(III) Complexes as Catalysts for Benzyl Alcohol Oxidation

“…The formation of the trans ‐[RuO 3 VI (OH) 2 ] 2− anion was confirmed by the presence of two bands at 368 nm and 462 nm in the electronic spectrum of the reaction mixture used in the catalytic oxidation process. These bands were close to those reported for the trans ‐[RuO 3 VI (OH) 2 ] 2− [48] . Another evidence, the cyclic voltammogram of complex ( Ru3 ) exhibited three oxidation waves at 0.192 V, 0.498 V, and 0.804 V, respectively (Figure 5b).…”

Investigation into the Nature of the Oxoruthenate Species used to Mediate the Oxidation of an Organic Substrate by Hypochlorite in a Biphasic System†

“…xH 2 O were obtained from Johnson Matthey and all other chemicals from Aldrich. Aqueous solutions of RuO 4 set at different pHs were prepared using the method of Bailey et al 7 The oxidation of octan-2-ol by hypochlorite in a biphasic system was monitored by gas chromatography using a procedure and equipment described by Giddings and Mills. 8…”

“…This process continues until the organic substrate has been completely oxidised, or the reaction is stopped. Recent work by Bailey et al 7 has identified many cases where the nature of the active catalyst in such biphasic systems was either not identified or the identification was questionable. In particular, these workers were able to show 7 that the actual oxoruthenate catalyst was usually RuO Most work on such RuO 4 catalytic biphasic systems employs sodium periodate in neutral solution as the inorganic oxidant: however, the latter is considered expensive and problems can be encountered with the precipitation of voluminous amounts of sodium iodate as the reaction proceeds.…”

“…Recent work by Bailey et al 7 has identified many cases where the nature of the active catalyst in such biphasic systems was either not identified or the identification was questionable. In particular, these workers were able to show 7 that the actual oxoruthenate catalyst was usually RuO Most work on such RuO 4 catalytic biphasic systems employs sodium periodate in neutral solution as the inorganic oxidant: however, the latter is considered expensive and problems can be encountered with the precipitation of voluminous amounts of sodium iodate as the reaction proceeds. 9 Prompted by these problems, in 1970 Wolfe and his co-workers 9 suggested that household bleach, i.e., sodium hypochlorite in alkali solution (typically 0.67 mol dm 3 NaOCl), acts as a suitable replacement for sodium periodate.…”

Synthesis, structure, catalytic and calculated non-linear optical properties of cis- and trans-, mer-chlorobis(triphenyl phosphine/triphenyl arsine)-dipicolinato rutheniumIII complexes

“…Amongst organic transformations, catalytic oxidation of alcohol to carbonyl compounds is an important reaction due to their utility in fine chemicals and pharmaceutical industries. Ruthenium complexes are known to mediate alcohol oxidation using variety of oxidants such as PhIO [11], NMO [12], BrO À 3 [13], S 2 O À 8 [14], t-BuOOH [15], and O 2 or air [16]. More recently, there has been an increased interest in mixedligand complexes containing both phosphine types of donors and N types of donors as a result of the unique electronic properties that this combination of ligands is able to transmit to the metal center [17][18][19][20][21][22].…”