Thiabenzene Oxide Complexes

Thiabenzene Oxide Complexes.—Reactions of l-methyl-3,S-diphenylthiabenzene-1-oxide (L) with (MeCN)aM(CO)3 (M = Cr, Mo, or W) have afforded complexes of the type LM(CO)s crystal-structure analyses have established that the cyclic ligand is non-planar with only the five carbon atoms bonded to the metal atom.  

Siebert, J. Edwin, and M. Bochmann, Angew. Chem. Internat, Edn., 1978, 17, 868. 

A review on the industrial applications of homogeneous catalysts is particularly welcome. The proceedings of recent symposia and a general text have been published in addition to reviews on metal cluster catalysts, activation of saturated hydrocarbons by metal complexes in solution, catalysis by arene Group-VIB tricarbonyls, titanocene-catalysed reactions ofalkenes, transition-metal hydrides in catalysis, the mechanisms of the catalytic cyclization of aliphatic, hydrocarbons, asymmetric hydrosilylation and asymmetric synthesis. A n.m.r. study of the conformations of chelated Diop and a MO study of organo-metallic migration reactions are also of interest. Polymer supported catalysts have been reviewed and the relationship between cross-linking of the polymer and catalytic activity has been discussed.  

Other more specific reviews are included at the beginning of the appropriate section and each section is arranged in Periodic Table order of the catalyst. 

The intermediate [PdCI(j7 -QHi3)PPh3] has been isolated from the [PdCl2-(PPh3)a]-catalysed hydrogenation of cyclo-octa-1,5-diene interestingly the rate of this reduction under hydrogen chloride gas is the same as that under hydro- 

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Methyl-3,5-diphenyl-l//-thiopyran 1-oxide forms red air-stable complexes with carbonyls of chromium, molybdenum and tungsten. (78CB1709). X-Ray diffraction measurements on these compounds confirm the non-planarity of the thiabenzene oxide nucleus and reinforce the evidence for high inversion barriers at sulfur. These complexes are found in isomeric forms with either the sulfur-oxygen bond axial to the half-chair conformation adopted by the ring, or the S- methyl group axial the complexes cannot be interconverted. 

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