Two derivatives of phenyltrisalanine, a new, trifunctional amino acid,
were synthesised in optically active forms. Two complementary techniq
ues were employed, an HWE olefination reaction or a Heck coupling reac
tion, and the resulting dehydroamino acids were hydrogenated using a c
hiral Rh(I)-Et-DuPHOS catalyst. Phenyltrisalanine derivatives of excel
lent stereoisomeric purities were thus obtained. (C) 1998 Elsevier Sci
ence Ltd. All rights reserved.