Thionyl Chloride → HCID 53970757, compound

Participants

Reaction Steps

FIG. 11 depicts a reaction scheme for the synthesis of 11-2b, 9-fluorenylmethoxy-carbonyl-norvalinol, a description of the synthesis of which follows. To a chilled solution of Fmoc-norvaline (25 g, 73.75 mmol) in anhydrous methanol (469 ml), was added thionyl chloride (53.76 ml, 737.5 mmol) over one hour. Thin layer chromatography in ethyl acetate after an hour confirmed the completion of the reaction (Rf=0.85). The reaction mixture was concentrated and the remaining residue was dissolved in ethyl acetate. The organic layer was washed with several 200 ml portions of saturated sodium bicarbonate followed by brine. The organic layer was dried and concentrated to afford the title compound 9-fluorenylmethoxy-carbonyl-norvaline methyl ester 11-2a as a white solid (26.03 g) in quantitative yield. NMR δ ppm (CD3OD): 7.7 (m, 2H), 7.6 (m, 2H), 7.4 (m, 2H), 7.3 (m, 2H), 4.3 (m, 2H), 4.1 (m, 2H), 3.7 (s, 3H), 1.7 (m, 1H), 1.6 (m, 1H), 1.4 (m, 2H), 0.95 (t, 3H).

Provenance & Evidence