3-bromo-7-chloro-5-methylpyrazolo[1,5-a]pyrimidine synthesis

Yield: 100%

Reaction Conditions:

with N-Bromosuccinimide at 20; for 16 h;

Steps:

5.1.7. General procedure for the synthesis of 3-bromo-7-chloro-5-methylpyrazolo (11a) and 3-bromo-7-chloro-2,5-dimethylpyrazolo[1,5-a]pyrimidine (11b)
General procedure: A solution of 10a or 10b (1 equiv) in dichloromethane was cooled to 0°C using an ice bath. N-bromosuccinimide (1.1 equiv) was added slowly to the solution that was stirred for 16 h at room temperature. The reaction mixture was washed diluted with water and the reaction mixture extracted with dichloromethane (3).The organic phase was dried over Na2SO4 and concentrated to yield the desired product as a yellow solid. 11a Yield = quantitative. dH(400 MHz; CDCl3) 8.13 (s, 1H), 6.88 (s, 1H), 2.63 (s, 3H). LCMS(ESI): m/z 247 [M+H]+11b Yield = quantitative. dH (400 MHz;CDCl3) 8.13 (s, 1H), 2.85 (s, 3H), 2.63 (s, 3H). LCMS (ESI):m/z261[M+H]+.

References:

Candice, Soares De Melo;Feng, Tzu-Shean;Van Der Westhuyzen, Renier;Gessner, Richard K.;Street, Leslie J.;Morgans, Garreth L.;Warner, Digby F.;Moosa, Atica;Naran, Krupa;Lawrence, Nina;Boshoff, Helena I.M.;Barry, Clifton E.;Harris, C. John;Gordon, Richard;Chibale, Kelly [Bioorganic and Medicinal Chemistry,2015,vol. 23,# 22,p. 7240 - 7250]