Phosphane tetraphosphane

With diphosphanes recently Stephan et al. reported an intriguing Al and P based macrocyclic structure [37]. A zirconium based catalyst precursor first was employed in the catalytic dehydrocoupling of the primary bidentate phosphane to give the tetraphosphane 6, (Scheme 4). The function of 6 as a molecular building block has been demonstrated by its reaction with MMe3(M = Al, Ga). Although, the gallium derivative 7 has not been... 

The main products under all variations of R and R are the P2-chlorinated triphosphanes. Side reactions such as SiMe3/Cl exchange, P—P cleavage by LiP(SiMe3)R, or transmetallations take place only to a small extent. MeP(SiMe3)2 is an exception inasmuch as it reacts with P-chlorinated phosphanes to yield tri- and even tetraphosphanes. 

The addition of 30% water by volume to acetone was found to create a simple polar-phase solvent system that produces 30-115% rate enhancements for the hydroformylation of 1 -hexene with a variety of monometallic rhodium phosphane catalysts, and a 265% rate increase for a dirhodium tetraphosphane catalyst possessing bridging and terminal carbonyl groups along with improved chemosdectivity to aldehyde products [31]. 

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