Triethylamine → 5-(4-Isopropylsulfonylphenyl)-3-[5-[4-[1-(methylamino)ethyl]phenyl]-1,3,4-oxadiazol-2-yl]pyrazin-2-amine

Participants

Reaction Steps

A mixture of 1-[4-[5-[3-amino-6-(4-isopropylsulfonylphenyl)pyrazin-2-yl]-1,3,4-oxadiazol-2-yl]phenyl]ethanone (130 mg, 0.2805 mmol), methylamine hydrochloride (37.88 mg, 0.5610 mmol), Ti(OiPr)4 (159.4 mg, 165.5 μL, 0.5610 mmol) and triethylamine (56.77 mg, 78.20 μL, 0.5610 mmol) was stirred at room temperature in ethanol (2 mL) under nitrogen overnight. The reaction mixture was treated with sodium borohydride (15.92 mg, 16.85 μL, 0.4208 mmol) and stirred at room temperature over weekend and then was quenched with aqueous ammonia (1 mL conc in 4 mL water). The mixture was extracted with dichloromethane and the organic extracts dried over MgSO4 and concentrated in vacuo. The residue was purified by reverse phase preparative HPLC [Waters Sunfire C18, 10 μM, 100 Å column, gradient 10%-95% B (solvent A: 0.05% TFA in water; solvent B: CH3 CN) over 16 minutes at 25 mL/min]. The product fractions were passed through a bicarbonate cartridge and concentrated in vacuo. The solid was triturated with acetonitrile to give the product as a pale yellow solid (27.0 mg, 22%); 1H NMR (400 MHz, DMSO) d 1.20 (d, 6H), 1.28 (d, 3H), 4.48 (m, 1H), 3.69 (q, 1H), 7.72 (d, 2H), 7.97 (d, 2H), 7.98 (v br s, 2H), 8.12 (d, 2H) and 9.07 (s, 1H) ppm; MS (ES+) 479.3

Provenance & Evidence