N-Substituted Ketimines

Cho and Chun reported an effective stoichiometric reduction of aromatic ketone N-phenylimines 63 using la-BHj or Za BHj to give the desired N-phenylamine 64 with good enantioselectivities (Table 11.10) [87]. The reduction was also effective when 0.1 equiv of la or 2a was used (runs 2 and 4). BHj THF as borane reagent in this reduction led to the J amine, whereas CB furnished the S amine (runs 8 and 9) [88]. For N-alkyl imine analogues, the reduction of N-tert-butyl imine of acetophenone provided 80% ee (run 12). However, reductions of other N-alkyl imine derivatives of the same ketone (runs 10, 11, 13 and 17) and N-phenyl or N-alkyl imine derivatives of 

The generous financial support of the Korea Research Foundation and the Research Grant from Hallym University is gratefully acknowledged. I would also thank all those who have contributed to the chemistry reviewed here, including those whose name appears in the references cited. 

For reviews, see (a) S. Itsuno, Org. React. 1998, 52, 395-576. (b) S. Itsuno, Comprehensive Asymmetric Catalysts E. N. Jacobsen, A. Pfaltz, H. Yamamoto (Eds), Springer-Verlag, New York, 1999 Volume 1, pp 289-315. (c) B. T. Cho, Y. S. Chun, Organob-oranesfor Syntheses (ACS Symposium Series 783), P. V. Ramachandran, H. C. Brown (Eds). American Chemical Society, Washington D.C., 2001, pp 122-135. 

Brunin, J. Cabou, S. Bastin, J. Brocard, L Pelinski, Tetrahedron Asymmetry 2002,13, 1241-1243. 

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