Asymmetric Mannich-type reaction of a chiral N-(tert-butylsulfinyl) ketimine with imines:: Application to the synthesis of chiral 1,3-diamines

Deprotonation of the chiral N-(tert-butylsulfinyl) ketimine 1 followed by trapping with imines 2 afforded the beta-amino imines 3 as the Mannich-type products in high diastereo-selectivities (99:1 dr). As versatile synthons chiral beta-amino imines 3 could be transformed into enantiomeric beta-amino ketone and chiral syn- or anti-1,3-diamines with high diastereomeric excess by hydrolysis or reduction, respectively. Moreover, the nucleophilic addition of organometallic reagents to chiral beta-amino imines 3 could provide 1,1,3-trisubstituted 1,3-diamines with high diastereoselectivities. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)