Angewandte Chemie International Edition
© WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Cover Picture (Angew. Chem. Int. Ed. Engl. 12/1990)
The cover picture shows the structure of a trigonal-bipyramidal rhodium complex, whose “beauty” stems from a chiral C3-symmetric triphosphane ligand (yellow, Rh; orange, CO; violet, P; black, C; white, H). The reduced number of asymmetric environs in mettal complexes with chiral tridentate C3-symmetric ligands should lead to high enatioselectivities in reactions which are catalyzed by such complexes. This was first achieved in the hydrogenation of olefins. To carry out organic reactions enantioselectively and catalytically is the ultimate aim of modern organic syntthesis. It can be achieved via the “bio-route” (enzyme-, antibody-catalyzed) and via the “metal-route” (Metal-complex-catalyzed). A contribution to the “metal-route” is described by M. J. Burk et al. on p. 1462. Cover picture computer graphic by J. C. Calabrese (DuPont Central Research & Development).