Cesium carbonate → 3-(4-Chlorophenyl)-2-(2-chlorophenyl)-7-(2,2,2-trifluoroethoxy)-pyrazolo[1,5-a]pyrimidine

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Reaction Conditions

Reaction Steps

To a mixture of 3-(4-chlorophenyl)-2-(2-chlorophenyl)-pyrazolo[1,5-a]pyrimidin-7-ol (I-12A-1a; 65 mg, 0.18 mmol) and Cs2CO3 (59 mg, 0.18 mmol) in DMF (1.5 ml) was added a DMF solution (0.1 ml) of trifluoromethanesulfonic acid 2,2,2-trifluoroethyl ester (42 mg, 0.18 mmol). After stirring at 60° C. overnight, the mixture was extracted from pH 7 water with ethyl acetate. The combined organic layers were washed with brine, dried (MgSO4) and then concentrated, in vacuo, to afford the crude product. Purification on a Chromatotron using 1:0:0, 20:1:0, and then 20:0:1 methylene chloride/ethyl acetate/methanol as eluants afforded, in addition to two N-alkylated isomers, product 12A-1 (16.5 mg, 21%) as a solid: +ESI MS (M+1) 438.4; 1H NMR (400 MHz, CD3OD) δ 8.56 (d, J=5.0 Hz, 1H), 7.55–7.41 (m, 6H), 7.24 (d, J=8.7 Hz, 2H), 6.80 (d, J=5.0 Hz, 1H), 5.16 (q, J=7.9 Hz, 2H).

Provenance & Evidence