(R)-3-(tert-butoxycarbonylamino)-4-(2,4,5-trifluorophenyl)butanoic acid → N-Boc-sitagliptin

Participants

Reaction Steps

The title compound was prepared from (3R)-3-[(1,1-dimethylethoxy-carbonyl)-amino]-4-(2,4,5-trifluorophenyl)butanoic acid (Intermediate 3, 50.1 mg, 0.15 mmol) and 3-(trifluoromethyl)-5,6,7,8-tetrahydro-1,2,4-triazolo[4,3-a]pyrazine (39.2 mg, 0.20 mmol) using a procedure analogous to that described for Example 1, Step C. The crude product was purified by preparative TLC (silica gel, 100% ethyl acetate) to afford the title compound (29 mg) as a solid. 1H NMR (500 MHz, CDCl3) δ 1.37 (s, 9H), 2.61˜3.00 (m, 4H), 3.92˜4.30 (m, 5H), 4.93 (s, 1H), 4.95˜5.12 (m, 1H), 5.22˜5.35 (br, 1H), 6.83˜6.95 (m, 1H), 7.02˜7.12 (m, 1H). LC/MS (M+1-t-Bu) 452.

Provenance & Evidence