反应详情

16 g of L-glutamic acid γ-benzyl ester and 11 g of phthalic anhydride, both finely powdered, were stirred in 20 ml of toluene at reflux temperature for 2 hours. 50 ml of toluene were added and the mixture was evaporated. A further 80 ml of toluene were then added and the mixture was left to crystallize. Recrystallization from toluene yielded 15 g of α(S)-(2-benzyloxycarbonylethyl)-1,3-dihydro-1,3-dioxo-2-isoindoleacetic acid of melting point 96°-98° C.; [α]D20 =-50.4° (c=1 in methanol).

1. temperatureat reflux temperature for 2 hours
2. customthe mixture was evaporated
3. additionA further 80 ml of toluene were then added
4. waitthe mixture was left
5. customto crystallize
6. customRecrystallization from toluene