Benzyl chloroformate → Methyl 2-(2-(((benzyloxy)carbonyl)amino)pent-4-ynamido)-4-methylpentanoate

To a solution of compound 2 (8.5 g; 31 mmol) in dry THF (100 mL) was added DIEA (16.02 g; 124 mmol) and the reaction mixture was stirred for 30 min at room temperature. Benzylchloroformate (6.87 g; 40.3 mmol) was added and stirring was continued at room temperature for 16 h. The solvent was removed on the rotary evaporator and the residue was taken up in ethyl acetate (150 mL) and washed sequentially with water (50 mL), 5% HCl (2×50 mL), and brine (50 mL). The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated to give 3 as a white solid (10.46 g: 90% yield). 1H NMR (CDCl3) δ 7.3 (m, 5H), 6.7 (s, 1H), 5.6 (s, 1H), 5.1 (s, 2H), 4.6 (m, 1H), 4.4 (m, 1H), 3.7 (s, 3H), 2.6 (m, 2H), 2.8 (s, 1H), 2.6 (m, 1H), 1.6 (m, 2H), 1.5 (m, 1H), 0.9 (d, 6H).

1. stirringstirring
2. waitwas continued at room temperature for 16 h
3. customThe solvent was removed on the rotary evaporator
4. washwashed sequentially with water (50 mL), 5% HCl (2×50 mL), and brine (50 mL)
5. dry with materialThe organic layer was dried over anhydrous sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated

ORD record

ord-74690623dbbd45ab9e778fee6483639e

Source dataset

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09309284B2