Trichloroacetonitrile → (+/-)-1-(3-Bromo-5-chloro-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-indazol-7-yl)ethyl 2,2,2-trichloroacetimidate

Participants

Reaction Conditions

Reaction Steps

(±)-1-(3-Bromo-5-chloro-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-indazol-7-yl)ethanol (1.29 g, 3.18 mmol) was dissolved in methylene chloride (10 mL), cooled to 0° C. and treated with 1,8-diazabicyclo(5.4.0)undec-7-ene (96 μL, 0.64 mmol). The reaction was stirred for 10 min and treated with trichloroacetonitrile (3.19 mL, 31.8 mmol) dropwise over 10 min. The ice bath was removed and the reaction stirred at room temperature for 1 h and concentrated. Flash chromatography on silica gel (5% ethyl acetate/hexanes) gave 1.69 g (77%) as an oil. 1H-NMR (CDCl3, 300 MHz) δ 8.27 (s, 1H), 7.59 (d, J=1.8 Hz, 1H), 7.53 (d, J=1.8 Hz, 1H), 6.58 (q, J=6.6 Hz, 1H), 6.19 (qAB, JAB=11.4 Hz, 2H), 3.50-3.56 (m, 2H), 1.74 (m, 3H), 0.80-0.84 (m, 2H), 0.06 (s, 9H).

Provenance & Evidence