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.
A simple and generalmethod for the asymmetric synthesis of α-aminophosphonic acids is described. A chiral phosphonate prepared in one step from R-(−)-phenylglycinol was alkylated with good diastereoselectivity using different electrophiles.
Electrophilic Amination and Azidation of Chiral α-Alkyl Phosphonamides: Asymmetric Syntheses of α-Amino α-Alkyl Phosphonic Acids†
作者:Stephen Hanessian、Youssef L. Bennani
DOI:10.1055/s-1994-25679
日期:——
Stereoselective electrophilic aminations of chiral non racemic α-alkyl phosphonamides, derived from N,N′-dimethyl (R,R)-1,2-diamino-cyclohexane, proceed with moderate to excellent enantioselectivities. The products are hydrolyzed and reduced to the corresponding α-alkyl α-amino phosphonic acids. The sense of asymmetric induction was confirmed by X-ray crystal structure analysis.
A versatile asymmetric synthesis of α-amino α-alkyl-phosphonic acids of high enantiomeric purity
作者:Stephen Hanessian、Youssef L. Bennani
DOI:10.1016/s0040-4039(00)97092-8
日期:1990.1
A general protocol for the synthesis of α-amino-α- alkyl phosphonic acids in either enantiomeric form is described based on the alkylation of chiral bicyclic phosphonamides derived from (R,R)- and (S,S)-1,2-diaminocyclohexane.