Synthesis of optically active arylene bis-alanine derivatives carrying orthogonal protecting groups

A Ritzén, B Basu, SK Chattopadhyay, F Dossa…

Index: Ritzen, Andreas; Basu, Basudeb; Chattopadhyay, Shital K.; Dossa, Fahreen; Frejd, Torbjoern Tetrahedron Asymmetry, 1998 ,  vol. 9,  # 3  p. 503 - 512

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Citation Number: 36

Abstract

Derivatives of para-and meta-phenylene bis-alanine and related biphenyl systems, carrying four orthogonal protecting groups, were synthesised via combinations of Heck couplings and asymmetric hydrogenations. The intermediate unsaturated arylalanine derivatives were hydrogenated using [Rh (COD)((R, R)-DIPAMP)]+ BF4− or [Rh (COD)(Me-DuPHOS)]+ X− as catalysts to produce the optically active, protected amino acid derivatives in≥ 98% ee as ...