Sodium methanethiolate → 3-[2(R)-tert-butoxvcarbonylamino-2-phenylethyl]-5-(2-fluoro-3-methoxyphenyl)-1-[2-fluoro-6-methylthiobenzyl]-6-methyl-pyrimidine-2,4(1H,3H)-dione

Participants

Reaction Conditions

Reaction Steps

To a solution of compound 6a (33 g, 56 mmol) in dry DMSO (100 mL) was added sodium thiomethoxide (4.0 g, 56 mmol) under nitrogen. The reaction mixture was heated to 100° C. under nitrogen for 1 hour. Another 0.28 eq. of sodium thiomethoxide (1.1 g, 16 mmol) was added, and the reaction mixture was heated to 100° C. under nitrogen for 1 hour. The reaction mixture was cooled and partitioned between ethyl ether and water. The organic layer was washed with saturated aqueous sodium bicarbonate solution and brine, dried with sodium sulfate, filtered and concentrated. The crude product was purified with a flash chromatography on silica gel eluted with 50% ethyl acetate in hexane to yield compound 6b as a pale yellow solid (27 g, 44 mmol, 78%). MS (CI) m/z 524.1 (M+H+-Boc), tR=3.134 min. (method 4). 1H NMR (CDCl3): δ 1.38 (s, 9H), 2.07 (s, 3H), 2.51 (s, 3H), 3.90 (s, 3H), 4.07–4.13 (m, 1H), 4.29–4.39 (m, 1H), 5.30–5.53 (m, 2H), 5.79–5.85 (m, 1H), 6.80–6.91 (m, 2H), 6.70 (dd, 1H), 7.06–7.15 (m, 2H), 7.22–7.41 (m, 6H).

Provenance & Evidence