Diphosphane monoxide

The hydrolysis of phosphinous amides leading to their constituents, amine and phosphinous acid, is an easy process that is usually followed by the selfcondensation of the acid to yield the diphosphane monoxides 21 [117, 118] (Scheme 21). 

This observation is unusual in diphosphanes, but rather normal in diphosphane monoxides, monosnlhdes, and monoselenides. Figure 5.29 gives the phosphorus... 

Enantioselective dicarboxylation of styrene with carbon monoxide and methanol in the presence of Pd[(R,R)-Diop](OOCCF3)2 /Sn(03SCF3)2 leads to dimethyl (/ )-phenylsuccinate in 29% yield and 30% ee. Using chiral diphenyl or binaphthyl diphosphane ligands (instead of Diop) increases the enantioselectivity to 82-93% ee (with 37-58% yields)45. 

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