反应详情

Dry methanol (200 ml) was saturated with HCl by bubbling in a three-necked round bottom flask and cooled to -10° C. p-Nitrophenylalanine (10.0 g, 47.6 mmol) was added in one portion and left to stir for two hours, then resaturated with HCl. The reaction flask was stoppered with a drying tube and left to stir at room temperature for 18 hours. The solution was evaporated to near dryness on a rotary evaporator and the precipitated product collected in a Buchner funnel. After drying under vacuum at 50° C., the yield of 1 was 10.97 grams (88.3%). A TLC of the free amino ester run in CHCl3 :MeOH (4:1) revealed an Rf =0.85-0.88. 1H NMR (220 MHz, D2O, pH 1.5) δ 8.20 (d, 2, J=10.0), 7.53 (d, 2, J=10.0), 4.55 (t, 1, J=11.0), 3.84 (s, 3), 3.43 (m, 2); CI-MS 225 ((M+1)/z).

1. customby bubbling in a three-necked round bottom flask
2. additionwas added in one portion
3. waitleft
4. customThe reaction flask was stoppered with a drying tube
5. waitleft
6. stirringto stir at room temperature for 18 hours
7. customThe solution was evaporated
8. customon a rotary evaporator
9. customthe precipitated product collected in a Buchner funnel
10. customAfter drying under vacuum at 50° C.