Investigation of the diastereoselectivity during the addition of an enantiomerically pure (2-lithiophenyl)acetaldehyde acetal to various imines

摘要

The diastereoselectivity during the addition of the homochiral (2-lithiophenyl)acetaldehyde acetal Ib to various imine components was investigated. The diastereoselectivity could be raised to 84.2% de by addition of Ib to benzylidenanisidine 2h. Removal of the tosyl and the p-methoxyphenyI protective groups of 3c, 4c and 3h/4h succeeded with sodium in liquid ammonia and ammonium cerium(IV) nitrate, respectively, to yield the enantiopure benzhydrylamines 5 and 6. [References: 15]