Enantioselective Synthesis of Diamino Dicarboxylic Acids.
The preparation of alkyl diamino dicarboxylic acids with high optical purity (100% ee, >98.5% de) and high yields based on asymmetric catalytic hydrogenation is described. The required prochiral precursors are prepared from dialdehydes and Z-, Boc-, and acetyl-protected phosphonoglycines. Aqueous solutions of glyoxal, succinic dialdehyde, and glutaric dialdehyde were used to prepare the diunsaturated precursors for 2,5-diaminoadipic acid (DAA), 2,7-diaminosuberic acid (DAS), and 2,8-diaminoazelaic acid (DAZ). Z-Protected dimethyl esters of DAA, DAS, and DAZ were obtained by hydrogenation of the corresponding prochiral starting materials with [(COD)Rh(S,S)-Et-DuPHOS]OTf.
Hiebl
Johann
J
Topcro Pharma Research GmbH, St. Peter Strasse 25, A-4020 Linz, Austria; Hafslund Nycomed Pharma AG, St. Peter Strasse 25, A-4020 Linz, Austria; and Nycomed Austria AG, St. Peter Strasse 25, A 4020 Linz, Austria.
Kollmann
Hermann
H
Rovenszky
Franz
F
Winkler
Karin
K