Diethyl Ether → HCID 59864982, compound

Participants

Reaction Steps

To a magnetically stirred and ice-cooled solution of 2-methyl-oct-2-en-4-one (9.30 gram, 63 mmol) in dichloromethane (90 ml) was slowly added bromine (3.23 ml, 33 mmol; dissolved in 10 ml dichloromethane) and the resulting mixture was stirred for 10 minutes. To the obtained mixture was slowly added triethylamine (13.10 ml, 94.5 mmol: dissolved in 25 ml dichloromethane). The resulting mixture was allowed to attain room temperature and stirred for 1 hour and subsequently stirred for 16 hours at 40° C. The obtained mixture was washed with 1N HCl (100 ml), dried over MgSO4, filtered and concentrated in vacuo to give crude 3-bromo-2-methyl-oct-2-en-4-one. Sepacore (40×300 mm column) separation (Gradient: first eluant: petroleum ether (40-60); second eluant: petroleum ether (40-60)/diethyl ether=98/2 (v/v)); third eluant: petroleum ether (40-60)/diethyl ether=95/5 (v/v)) gave 3-bromo-2-methyl-oct-2-en-4-one (Intermediate IIIc-1) pale-yellow oil (11.80 gram, 77% yield). 1H-NMR (400 MHz, CDCl3) δ 0.92 (t, J=7.2 Hz, 3H), 1.29-1.39 (m, 2H), 1.56-1.66 (m, 2H), 2.00 (br s, 6H), 2.78 (t, J=7.4 Hz, 2H).

Provenance & Evidence