Triethylamine → (Z)-Dec-4-en-1-yl methanesulfonate

To a cooled solution (0° C.) of (Z)-dec-4-en-1-ol 9 (20 g, 128.0 mmol) and triethylamine (26.7 mL, 191.9 mmol) in anhydrous dichloromethane (200 mL) was slowly added methane sulfonyl chloride (14.9 mL, 191.9 mmol). The solution was stirred for 30 min at room temperature then diluted with dichloromethane (100 mL). The solution was washed with saturated sodium bicarbonate (3×150 mL) and then the combined aqueous washes were extracted with dichloromethane (150 mL). The combined dichloromethane extracts were dried on magnesium sulfate, filtered and concentrated in vacuo to dryness. The residue was filtered through a pad of silica (100% dichloromethane) to afford (Z)-dec-4-enyl methanesulfonate 2 as a yellow oil (28.5 g, 95%). Rf 0.5 (100% CH2Cl2).