Dimethyl Sulfoxide → (S)-2-(dibenzylamino)butanal

関与物質

反応手順

A 2M solution of oxalyl chloride in dichloromethane (3.18 ml, 6.36 mmol) was cooled to −78 0° C. and diluted with dry dichloromethane (20 ml) under dry nitrogen. A solution of dimethylsulfoxide (1 g, 12.72 mmol) in anhydrous dichloromethane was added dropwise to the cooled stirred solution. The reaction was stirred for a further 1 h after completion of addition. A solution of (S)-2-(dibenzylamino) butan-1-ol (1.43 g, 5.3 mmol) in dichloromethane was added over 5 minutes. After 10 minutes, diisopropylethylamine (2.73 g, 21.2 mmol) was added. The reaction was allowed to warm to room temperature and left stiffing for 1 h. It was cooled to 0° C. and ethyl acetate/water (50 ml: 50 ml) was added. The organic layer was washed with water (50 ml), brine (50 ml) dried (MgSO4) and concentrated. The product was purified by flash silica column chromatography (ethyl acetate:Hexane 1: 4) to provide the pure product (1.28 g, 90.5%). δH (250 MHz, CDCl3) 0.88 (3 H, t, J 7.5, CHCH2CH3), 1.77-1.54 (2 H, m, CH2CH3), 2.99 (1 H, t,J 7.5, CHCH2CH3), 3.74-3.57 (4 H, m, 2×CH2Ph), 7.31-7.11 (10 H, m, 2×C6H5) 9.64 (1 H, s, CHO); δC (250 MHz, CDCl3) 203.9 (CO), 139.33 (2×C), 128.99 (4×CH), 128.45 (4×CH), 127.3 (2×CH), 68.46 (CH), 54.85 (CH2), 17.44 (CH2), 11.83 (CH3); m/z 268.2 (M+H)

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