An enantioselective synthetic method for alpha-alkylserines by the phase-transfer catalytic alkylation of 2-phenyl-2-oxazo-line-4-carbonylcamphorsultam (4a) was developed. The phase-transfer catalytic alpha-alkylation of 4a using P2-Et at -78 degrees C gave alpha-alkylation (75 similar to 99%, 90 similar to 97% de), which could be easily hydrolyzed to alpha-alkylserines.