反应详情

To a solution of trimethylsilyidiazomethane (1.24 mL of a 2M solution in hexane, 2.5 mmol) in 12 mL of tetrahydrofuran at −100° C. was added n-butyllithium (1.01 mL of a 2.5 M solution in hexane, 2.5 mmol). After stirring for 30 min, the solution was transferred via an insulated cannula to a −100° C. solution of N-BOC (D)-pyroglutamic acid methyl ester (0.50 g, 2.1 mmol) in 21 mL of tetrahydrofuran. After stirring for 20 min, the mixture was poured into saturated aqueous NH4Cl, extracted twice with ethyl acetate, and the combined organic layers were dried over Na2SO4, filtered and concentrated, affording 0.62 g of 2-tert-butoxycarbonylamino-5-diazo-4-oxo-pentanoic acid methyl ester as a yellow oil.

1. customwas transferred via an insulated cannula to a −100° C.
2. stirringAfter stirring for 20 min
3. extractionextracted twice with ethyl acetate
4. dry with materialthe combined organic layers were dried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated