Dihydro-alpha-ionone → HCID 20531507, compound

Participants

Reaction Steps

A solution of sodium bromide (6.17 g) in water (10 ml) and commercial bleach (31.2 ml of a solution of sodium hypochlorite) were stirred together for 5 minutes and a solution of dihydro-α-ionone (3.88 g) in methylene chloride was added. Then a solution of potassium phosphate (monobasic) (5.44 g) in water (30 ml) was added during 30 minutes. After stirring for 50 minutes at 25° a solution of sodium bromide (2.05 g) and commercial bleach (10 ml) was added, followed by a solution of potassium phosphate (monobasic) (2.72 g) in water (10 ml) and the reaction mixture stirred for 15 minutes at 25°. The methylene chloride solution was washed with sodium bicarbonate solution and the solvent evaporated to provide the crude product (5.86 g). Column chromatography gave 1.87 g of 4-(5-bromo-6-methylene-2,2-dimethylcyclohexyl)-2-butanone. NMR (CDCl3) δ0.93 (6H, s, >C(CH3)2), 0.9-2.6 (9H, m), 2.12 (3H, s, --COCH3), 4.6-5.1 (1H, m, >CHBr), 4.76 and 5.28 (2H, 2s, >C=CH2), 4.68 and 5.20 (2H, 2s, >C=CH2, minor isomer; isomer ratio 3/1). IR (film) νmax 2960, 1720, 1675, 1650, 1455, 1360.

Provenance & Evidence