Ozone → 4-[2-(4-tert-Butyl-phenyl)-3H-imidazo[4,5-c]pyridin-7-yl]-piperazine-1-carboxylic acid benzyl ester

Participants

Reaction Conditions

Reaction Steps

2,5-Dihydro-pyrrole-1-carboxylic acid benzyl ester 6 was dissolved in DCM (5 ml) and MeOH (2 ml). It was cooled to −78° C. and treated with ozone until it was blue in color. Triethyl phosphite (246 mg, 1.48 mmol) was added and the solution was allowed to stir for 5 minutes. 2-(4-tert-Butyl-phenyl)-1H-imidazo[4,5-c] pyridin-7-ylamine 4 (266 mg, 1.00 mmol) was added followed by sodium triacetoxyborohydride (538 mg, 2.54 mmol). This mixture was allowed to stir for 18 hours. Mass spectroscopy showed no starting material left after this time, and the solvent was removed under vacuum. The crude was taken up in ethyl acetate and washed with a saturated sodium bicarbonate solution, brine, dried over MgSO4, and the crude was purified by HPLC (Method E), yielding the title product 7 (12 mg (2.5%), 0.026 mmol). 1H NMR (DMSO-d6): δ 8.88 (bs, 1H), 8.23 (d, J=8.5 Hz, 2H), 7.96 (s, 1H), 7.68 (d, J=8.5 Hz, 2H), 7.38 (m, 5H), 5.15 (s, 2H), 1.33 (s, 9H). MS (ESI-POS): [M+H]+=470; MS(ESI-NEG):[M−H]−=468.

Provenance & Evidence