A Convenient Method for the Synthesis of Cprotected Esters of Boc- / Z-α,α- Dialkylamino Acids by the Mixed Carboxylic - Carbonic Anhydride Method

The synthesis of C-protected esters of Boc- / Z-α,α-dialkylamino acids is accomplished by using alkyl / aryl chloroformate in presence of DMAP as a catalyst. The reaction proceeds through mixed carboxylic-carbonic anhydride, which was monitored by IR. The reaction was clean and complete in about 2 hr. All the esters prepared have been obtained in good yield and are fully characterized.