[reaction: see text] A racemic aldehyde can undergo parallel kinetic resolution (PKR) by simultaneous reaction with two different chiral phosphonates, differing either in the structure of the chiral auxiliary or in the structure of the phosphoryl group (i.e., one (E)- and one (Z)-selective reagent). This strategy allows conversion of a racemic aldehyde to two different, synthetically useful chiral products with essentially doubled material throughput and similar or improved selectivities as compared to conventional kinetic resolution.

2000 stereochemistry stereochemistry (general, optical resolution) O 0030 -043Parallel Kinetic Resolution of Racemic Aldehydes by Use of Asymmetric Horner-Wadsworth-Emmons Reactions.-The parallel kinetic resolution allows efficient conversion of a racemic aldehyde to two different chiral products of high isomeric purity. This can be accomplished either by using two chiral phosphonate reagents containing different chiral auxiliaries or by using one (Z)-selective and one (E)-selective reagent bearing the same auxiliary. -(PEDERSEN, TORBEN M.; JENSEN, JAKOB F.; HUMBLE, RIKKE E.; REIN, TOBIAS; TANNER, DAVID; BODMANN,