(3R,4S)-3-乙基-4-(羟甲基)环戊烷-1-one

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a solution of (3R,4S)-3-ethyl-4-(hydroxymethyl)cyclopentanone (2.60 g, 18.3 mmol) in DMF (30 mL) was added imidazole (1.87 g, 27.4 mmol) followed by tert-butylchlorodimethylsilane (3.03 g, 20.1 mmol). After about 4 h, heptane (50 mL) was added. The heptane layer was removed and washed with brine. The brine layer was combined with the DMF layer and extracted with EtOAc/heptane (1:1, 30 mL). The heptane and EtOAc layers were combined, concd in vacuo and purified by chromatography on silica gel eluting with EtOAc/heptane (0-30%) to provide (3S,4R)-3-((tert-butyldimethylsilyloxy)methyl)-4-ethylcyclopentanone (3.5 g, 75%) as a colorless oil. 1H NMR (400 MHz, CDCl3) δ 3.77 (dd, J=10.5, 4.3 Hz, 1H), 3.64 (dd, J=10.5, 4.0 Hz, 1H), 2.40-2.20 (m, 5H), 2.18-2.02 (m, 1H), 1.65-1.55 (m, 1H), 1.52-1.37 (m, 1H), 0.97 (t, J=7.4 Hz, 3H), 0.87 (s, 9H), 0.43 (s, 3H), 0.03 (s, 3H). The heptane layer was removed washed with brine extracted with EtOAc/heptane (1:1, 30 mL) purified by chromatography on silica gel eluting with EtOAc/heptane (0-30%)

反应条件: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a solution of (3R,4S)-3-ethyl-4-(hydroxymethyl)cyclopentanol (4.00 g, 27.7 mmol) in MeCN (70 mL) and water (30.0 mL) was added potassium bromate (1.487 mL, 29.1 mmol) and CAN (0.760 g, 1.387 mmol). The reaction mixture was heated to about 80° C. After about 2 h, the reaction mixture was cooled to rt and Et2O (100 mL) was added. The organic layer was separated, washed with brine (30 mL), concd in vacuo and purified by chromatography on silica gel eluting with EtOAc/heptane (20-60%) to provide (3R,4S)-3-ethyl-4-(hydroxymethyl)cyclopentanone (2.4 g, 61%) as an oil. 1H NMR (400 MHz, CDCl3) δ 3.79 (dd, J=10.5, 5.3 Hz, 1H), 3.70 (dd, J=10.5, 6.5 Hz, 1H), 2.55-2.44 (m, 1H), 2.41-2.25 (m, 4H), 2.15-2.05 (m, 1H), 1.55-1.65 (m, 2H), 1.43-1.30 (m, 1H), 0.97 (t, J=7.3 Hz, 3H). the reaction mixture was cooled to rt The organic layer was separated washed with brine (30 mL), concd in vacuo purified by chromatography on silica gel eluting with EtOAc/heptane (20-60%)