Dimethyl Sulfoxide → 1-Cyclohexyl-2-phenylpropan-1-one

Beteiligte Stoffe

Reaktionsschritte

DMSO (118 mL, 1.6674 mol) was added dropwise to a solution of 126.42 g (0.579 mol) of 1-cyclohexyl-2-phenylpropanol in 1737 mL of CH2Cl2 (cooled in a wet ice acetone bath). After 29 min, 147.93 g (1.0422 mol) of P2O5 was added. After 11 min, the cooling bath was removed. An aliquot quenched with Et3N showed complete reaction within 3 h at RT. The reaction mixture was cooled in a wet ice acetone bath. Et3N (282 mL, 2.0265 mol) was added dropwise to the cooled reaction mixture over a 30 min period. The cooling bath was removed and the mixture was stirred overnight at RT. The reaction mixture was quenched by dropwise addition of 500 mL of 3 N HCl (aq) (pH=0). After shaking in separatory funnel, the aqueous phase was removed. The organic phase was washed with 500 mL of 3 N HCl (aq) (pH=0), washed twice with 1 L of 10% K2CO3 (aq) (pH=12;12), washed three times with 500 mL of NaOCl (aq) solution, washed with 1L of water, washed with 1 L of 25% NaCl (aq), dried over MgSO4, gravity filtered and concentrated under vacuum with dry ice trap to collect Me2S. An amber oil of the title compound (107.01 g, 85.437%) was obtained; 1H NMR (d6-DMSO) δ 7.30-7.37 (m, 2H, phenyl CH), 7.21-7.28 (m, 3H, phenyl CH), 4.08 (q, J=6.9 Hz, 1H, —CH(CH3)Ph), 2.40-2.49 (m, 1H, cyclohexyl CH), 1.82-1.84 (m, 1H, cyclohexyl —CH2), 1.67-1.69 (m, 1H, cyclohexyl —CH2), 1.52-1.63 (m, 1H, cyclohexyl —CH2), 1.34-1.43 (m, 1H, cyclohexyl —CH2), 1.26 (d, J=6.9 Hz, 3H, —CH(CH3)Ph), 1.01-1.24 (m, 4H, cyclohexyl —CH2).

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