Reaction Mechanism for the Zinc Acetylide Addition to Amino Ketone

2 Reaction Mechanism for the Zinc Acetylide Addition to Amino Ketone 36 

Nonlinearity was also found for this asymmetric organozinc addition, for example, using 50% ee of chiral modifier 46 resulted in 80% ee of adduct 53. The enanti-oselectivity is also dependent on the reaction concentration 98% ee was obtained at 0.1-0.5 M but only 74% ee at 0.005 M. Kitamura and Noyori s work strongly suggested that heterodimer 72 might be more thermally stable than the homodimer 

The authors would like to thank all colleagues who worked on this project, whose names are listed in the references. The authors would also like to thank Dr. James McNamara for his careful proofreading and helpful suggestions. 

7 Recently asymmetric Strecker reaction with ketone is reported (a) Vachal, P., and Jacobsen, E.N. (2002) J. Am. Chem. Soc., 124, 10012-10014. (b) Masumoto, 

11 March, J. (1985) Advanced Organic Chemistry, 3rd edn, John Wiley Sons, Inc., p. 485. 

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