Dibromomethane → 1-Bromo-2-cyano-2-(2-ethoxyphenyl)heptane

Participants

Reaction Steps

A 200 ml three-neck flask fitted with a reflux condenser, nitrogen inlet, thermometer and addition funnel was charged with 1.8 grams (0.045 moles, 1.28 ec.) of 60% NaH, washed 2×40 ml of hexane, in 30 ml of dimethyl formamide (DMF). While stirring at room temperature, 1.41 grams of 35% KH (with removal of the mineral oil before washing with hexane, assumed 100% KH, 0.035 moles, 1.0 ec.) in 20 ml of DMF was added. To the reaction was added 8.10 grams (0.0350 moles, 1.0 ec.) of 2-(2-ethoxyphenyl)heptanenitrile in 25 ml of DMF. After stirring at room temperature for 1 hour, 9.15 grams (0.0525 moles, 1.5 eg.) of CH2Br2 in 25 ml of DMF was added dropwise over 10 minutes. The reaction exothermed slightly and was stirred at room temperature overnight after which GLC indicated the reaction was 80% product. An additional 0.7 g of 100% KH (0.5 ec.) was added in 20 ml of DMF, after washing with 20 ml of hexane, and this was followed by an additional 3.0 grams of CH2Br2The reaction was stirred for an additional 3 hours and was complete by GLC. Workup with ether and water gave after concentration 10.97 grams of a thick oil (97.2% yield) which was used directly in the coupling procedure.

Provenance & Evidence