Potassium bisulfate → (Rs)-2-(4,4-dimethyl-thiochroman-6-yl)-heptanal

Participants

Reaction Conditions

Reaction Steps

0.49 g of (RS)-N-methoxy-N-methyl-2-(4,4-dimethyl-thiochroman-6-yl)-heptanoic amide was dissolved in 5 ml THF and treated with 1.6 ml of 1M lithium aluminium hydride solution in THF at −40° C. The mixture was stirred at −40° C. for 30 min. then allowed to warm to room temperature over 1.5 hour. The mixture was cooled back to −40° C. and 3.5 ml of 20% aqueous KHSO4 solution was added over 5 min. The mixture was stirred at room temperature for one hour. The reaction mixture was partitioned in 100 ml ethyl acetate/50 ml water and the phases were separated. The aqueous phase was extracted with three portions of 15 ml of ethyl acetate. The combined organic extracts were washed with one portion of 25 ml of water, one portion of 25 ml of 1 N hydrochloric acid, one portion of 25 ml of saturated aqueous sodium bicarbonate solution and one portion of 25 ml of saturated aqueous sodium chloride solution. The organic phase was dried over MgSO4 and concentrated in vacuo, giving 0.35 g of the titled compound which was used without purification. 1H NMR (CDCl3): 9.61 (d, J=2.2 Hz, 1H), 7.13 (d, J=2.0 Hz, 1H), 7.08 (d, J=8.1 Hz, 1H), 6.86 (dd, J=8.1, 2.0 Hz, 1H), 3.45-3.35 (m, 1H), 3.05-3.00 (m, 2H), 2.10-1.90 (m, 3H), 1.70-1.50 (m, 1H), 1.32 (s, 6H), 1.35-1.20 (m, 6H), 0.86 (br.t, J=6.7 Hz, 3H).

Provenance & Evidence