Binaphthol hydrocyanation

Draw structures of ligands derived from the chiral framework of glucose, tartaric acid, binaphthol, and cinchona alkaloids that are used for efficient asymmetric hydrocyanation, epoxidation, hydroformylation, and alkene dihydroxylation reactions respectively. 

A chelating diphosphite prepared from biphenol and PCI3 provides a very stable Ni(0) complex that catalyzes the hydrocyanantion of butadiene without excess ligand. Although the stability of this catalyst is enhanced, the amount of butadiene dimerization byproducts is significant. A related nickel catalyst prepared using a chiral chelating diphosphite based on I -2,2 -binaphthol provides enantioselectivity in the hydrocyanation of norbomene. The major product, J -exo-2-cyanonorbomane, was obtained in an enantiomeric excess of up to 38%. 

Similar results for the asymmetric hydrocyanation of norbornene (up to 70% yield with up to 38% ee) were obtained using an air-stable chirally modified Ni(0)L2 complex as the catalyst precursor39. The chiral (7 )-2,2 -binaphthol-derived aryl diphosphite (L1), contains three 1,1 -binaphthyl units. Its Ni(0)L2 complex is prepared from Ni(cod)2 and can be activated with trip hen ylboron39. Use of a similar chiral monophosphite ligand [L2, also derived from (/ )- 2,2 -... 

Miscellaneous.- New optically active phosphites (103) and (104) derived from R- or 5-2,2 -binaphthol have been prepared by standard methods and used as ligands for asymmetric hydroformylation or hydrocyanation reactions. Low to moderate asymmetric induction was achieved in the synthesis of S,6-disubstituted cyclohexadienes from benzene chromium complexes when the optically active phosphites (105) were ligands. ... 

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