Transition metals in organic synthesis: Hydroformylation, reduction, and oxidation

Design and Enantioselective Synthesis of a Peptidomimetic of the Turn in the Helix−Turn−Helix DNA-Binding Protein Motif

“…Stereoselective amino acid synthesis has been reviewed . The turn mimic is an example of the less common side-chain bridged α,ω-diaminodicarboxylates, of which there are many examples, − but few that are carbon−carbon linked. , Synthesis of unnatural amino acids was greatly advanced by the development of stereoselective catalysts for the hydrogenation of didehydroamino acids. − A C 2 -symmetric chiral catalyst, rhodium 2( S ),5( S )-dimethyl-1,2-bisphospholanobenzene (MeDUPHOS), cleanly reduces didehydroamino acids to the corresponding l -amino acid in high yield and high enantioselectivity. − Synthesis of the precursor didehydroamino acids was facilitated by the development of an α-amino acid Horner−Wittig reagent . The Wittig reaction and Horner−Wadsworth−Emmons modifications were reviewed in 1989 …”

“…18,19 Synthesis of unnatural amino acids was greatly advanced by the development of stereoselective catalysts for the hydrogenation of didehydroamino acids. [20][21][22] A C 2 -symmetric chiral catalyst, rhodium 2(S),5(S)-dimethyl-1,2-bisphospholanobenzene (MeDUPHOS), cleanly reduces didehydroamino acids to the corresponding L-amino acid in high yield and high enantioselectivity. [23][24][25] Synthesis of the precursor didehydroamino acids was facilitated by the development of an R-amino acid Horner-Wittig reagent.…”