Ethyl chloroformate → HCID 72192937, compound

Participants

Reaction Steps

To a stirred solution of compound 3 (0.400 g, 1.40 mmol, 1.00 equiv) in methanol (10 mL) was added zinc powder (0.470 g, 7.10 mmol, 5.00 equiv) followed by ammonium chloride solution (0.380 g, 9.10 mmol, 5.00 equiv) drop wise. After being stirred for 5 h at RT, DIPEA (0.155 g, 1.54 mmol, 1.10 equiv) and ethyl chloroformate (0.151 g, 1.40 mmol, 1.00 equiv) were added to reaction mixture at 0° C. and the stirring was continued for another 3 h at RT. After consumption of the starting material (by TLC), the reaction mixture was diluted with water (25 mL) and Extracted with EtOAc (2×75 mL). The separated organic layer was dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure to give crude; which was purified by silica gel column chromatography (EtOAc/Hexane 1:4) to afford to compound 3A (0.100 g, 21.0%) as brown solid. TLC: 40% EtOAc/Hexane (Rf: 0.50); 1HNMR (400 MHz, DMSO-d6): δ 8.27 (br s, 1H), 7.39-7.34 (m, 2H), 7.12 (t, J=8.8 Hz, 2H), 6.81-6.78 (m, 1H), 5.93 (d, J=9.2 Hz, 1H), 5.79 (t, J=6.4 Hz, 1H), 4.42 (s, 2H), 4.22 (d, J=6.0 Hz, 2H), 4.03 (q, J=6.8 Hz, 2H), 1.19 (t, J=6.8 Hz, 3H); LC-MS: m/z=322 (M++1) at RT 3.54 (95.8% purity); UPLC purity: 98.8%

Provenance & Evidence