Rhodium phosphabenzenes

Breit B, Winde R, Mackewitz T, Paciello R, Harms K. Phosphabenzenes as monodentate 7t-acceptor ligands for rhodium-catalyzed hydroformylation. Chem A Eur J 2001 7(14) 3106-21. 

Interest in the chemistry of the 6ji-phosphinine (phosphabenzene) system has continued, although considerably fewer papers have appeared compared to recent years. The synthesis, coordination chemistry and catalytic applications of phosphi-nines have been reviewed." New chiral bidentate phosphinine ligands (220) have been prepared and their coordination chemistry and applications in rhodium-catalysed asymmetric hydrogenations assessed." The diphosphinine (221) continues to find new applications as a ligand in homogeneous catalysis" and a new mode of coordination to a metal has been identified for the phosphinine (222), two such ligands simultaneously bridging a Mn-Mn bond." ... 

Phosphabenzenes can be hydrogenated with a homogeneous rhodium catalyst to give 2,6-diaryl-substituted phosphacyclohexanes of type I, as exemplarOy illustrated in Scheme 2.11 [37]. There was no need to isolate the products since rhodium-containing hydrogenation solutions could be directly submitted to the... 

Breit B, Winde R, Harms K (1997) Phosphabenzene-rhodium catalysts for the efficient hydroformylation of terminal and internal olefins. J Chem Soc Perkin Trans 18 2681-2682... 

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