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Please login or sign up for a free trial to access the full content. Use of Chiral Titanium Complexes as Catalysts

DOI: 10.1055/sos-SD-119-00001

Wang, W. T.; Lin, L. L.; Liu, X. H.; Feng, X. M.Science of Synthesis Knowledge Updates, (20114435.

Asymmetric cyanation of a class of easily available alkylidenemalonates with a favorable cyanide source, ethyl cyanoformate, has been realized by Feng and co-workers, employing an interesting modular titanium catalyst constructed from alkaloid 114 and ligand 115 or 116 (Scheme 55).[‌93‌] High yields and enantiomeric excess values are obtained for nitriles 117 obtained from a range of substrates under solvent-free conditions at 0°C. The products obtained can be easily transformed into the enantioenriched pharmaceutically important γ-aminobutanoic acids (Scheme 55).

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