of methylcyclopropanone acetal (2S)-4b with chiral amines and a trialkyl phosphite has been devised, by means of which the amino phosphonate esters 8 are obtained with excellent diastereoselectivities. Catalytic hydrogenolysis and hydrolysis of these phosphonates gives (1S,2S)-1-amino-2-methylcyclopropanephosphonic acid 1b in good overall yield and with excellent enantiomeric excess.
Synthesis of (1S,2S)- and (1R,2R)-1-amino-2-methylcyclopropane-phosphonic acids from racemic methylcyclopropanone acetal
作者:Nicolas Tesson、Benoist Dorigneux、Antoine Fadel
DOI:10.1016/s0957-4166(02)00609-2
日期:2002.10
An efficient and easy one-pot reaction from readily available racemic alkylcyclopropanone acetals gave the corresponding aminophosphonates with excellent diastereoselectivity. After catalytic hydrogenolysis, and hydrolysis, these trans-phosphonates led to enantiopure (+)-1-amino-2-methylcyclopropanephosphonic acid and its antipode (analogues of allo-norcoronamic acid).