Ruthenium complexes carbonyl bromides

Treatment of [Co(CO)4] under PT conditions with a mixture of alkyne and Mel (excess) in a CO atmosphere gives hydroxybut-2-enolides (eq. (12)) [148]. When benzyl bromide is used instead of Mel, the but-2-enolides are not formed due to the fast hydrolysis of the acylcobalt carbonyl intermediate [PhCH2COCo(CO)4] before the alkyne complex is formed. This obstacle has been overcome by carrying out the reaction in the absence of water, using solid/liquid PTC [149]. The direction of the PTC carbonylation of alkynes in the presence of Mel changes again when cobalt and ruthenium carbonyls are used simultaneously (1 1) [150]. In this case, y-ketoacids are obtained. 

Jn a potentially far reaching application for melt catalysis by the transition metals, we at Texaco have demonstrated the synthesis of a range of commodity chemicals and fuels directly from CO/H2 via the use of ruthenium-containing molten salt catalysis. Products include ethylene glycol, Ci-C4 alcohols, acetic acid, acetate esters, C2+ olefins and vicinal glycol esters. In its simplest form, this new class of melt catalyst comprises one or more ruthenium sources, e.g. ruthenium carbonyls, oxides, complexes, etc. dispersed in a low-melting (m.p. <150 C) quaternary phosphonium or ammonium salt (e.g. tetrabutylphos-phonium bromide). The key components are selected such that ... 

Ruthenium(II), d, is known as the binary bromide and as [RuCU] ". The richer complex chemistry involves stable compounds with cyanide, amines, halides, water, nitrosyl, carbonyl, hydride, phosphine, arsine, stibine, arene, and cyclopentadienyl ligands. [RuCl2(PPh3)2] is used as a catalyst. Ruthenium(II) is a good itt-donor and... 

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