1-aminophosphonic acids or reacted with Boc2O to yield N-Boc-protected 1-aminophosphonates. The enantiomers of 2-benzylthio-1-(t-butoxycarbonylamino)propylphosphonate were obtained from the racemate by chiral HPLC and converted to phosphonic acidanalogs of (R)- and (S)-homocysteine, (R)- and (S)-2-aminobutyric acid and (S)-methionine, all of ee >97% as determined by chiral HPLC.
(<i>E</i>)-2-Boryl 1,3-Dienes from the 10-TMS-9-BBDs: Highly Selective Reagents for the Asymmetric Synthesis of <i>anti</i>-α,β-Disubstituted β-Allenylamines from the Allylboration of Aldimines
作者:Javier R. González、John A. Soderquist
DOI:10.1021/ol501892a
日期:2014.7.18
The asymmetric allylboration of N-H aldimines with optically pure trans-4-substituted-2-boryl-1,3-dienes 6 is described. These organoboranes 6 serve as near-perfect asymmetric allylborating agents for N-H aldimines for the preparation of anti-1,2-disubstituted-3,4-pentadien-1-amines 11 as essentially single diastereomers in enantiomerically pure form (>98% de, ≥98% ee). Enantiomerically pure cis-2