4-Methylmorpholine → HCID 40428773, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of N-(9-fluorenylmethoxycarbonyl)-γ-t-butyl glutamic acid (8.51 g, 20.0 mmol) and NMM (2.42 mL, 1.1 eq) in dry THF (110 mL) under N2 at 0° C. was added isobutyl chloroformate (2.72 mL, 1.05 eq). After 20 min., the reaction e was filter-added to a solution of NaBH4 (1.5 g) in THF (120 mL)-MeOH (30 mL) at −78° C. under N2 and rinsed with dry THF (20 mL). After stirring for 2.5 h at −78° C., the reaction was quenched with acetic acid (13 mL). After concentrating to ˜50 mL, the residue was dissolved in ethyl acetate-hexanes (200 mL, 1:1), washed with water (150 mL×2). Aqueous layer was re-extracted with ethyl acetate-hexanes (150 mL, 1:1). Combined extract was washed with sat'd NaHCO3 (150 mL×2), dried (anhydrous Na2SO4), filtered and concentrated to give 8.30 g of the title compound as glasslike solid. The crude alcohol was used directly.

Provenance & Evidence