Toluene → HCID 117925887, compound

Participants

Reaction Steps

A mixture of 7-ethyl-5-(pyridin-2-yl)pyrido[2,3-d]pyridazin-8(7H)-one RL-8 (90 mg, 0.36 mmol), 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide (145 mg, 0.36 mmol), and toluene (8 mL) was heated to 115° C. for 3.5 h. After cooling to ambient temperature, the reaction mixture was diluted with 20 mL of ethyl acetate and washed with a 1:1 solution of saturated brine/1 N NaOH. The organic phase was dried over anhydrous magnesium sulfate, filtered, concentrated under reduced pressure and purified by normal phase flash chromatography eluting with 0-10% methanol in dichloromethane over 22 minutes. Like fractions containing the desired product were pooled, concentrated under reduced pressure, and dried overnight at 60° C. under vacuum to give 7-ethyl-5-(pyridin-2-yl)pyrido[2,3-d]pyridazine-8(7H)-thione RL-9 (52 mg, 0.20 mmol). 1H NMR (400 MHz, DMSO-d6) δ 9.17 (dd, J=4.3, 1.7 Hz, 1H), 8.98 (dd, J=8.3, 1.7 Hz, 1H), 8.77 (ddd, J=4.8, 1.7, 1.0 Hz, 1H), 8.08-7.97 (m, 2H), 7.91 (dd, J=8.3, 4.3 Hz, 1H), 7.59 (ddd, J=7.3, 4.8, 1.5 Hz, 1H), 4.86 (q, J=7.1 Hz, 2H), 1.45 (t, J=7.1 Hz, 3H).

Provenance & Evidence