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

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)

1. stirringThe reaction was stirred for a further 1 h
2. additionafter completion of addition
3. waitleft
4. waitstiffing for 1 h
5. temperatureIt was cooled to 0° C.
6. washThe organic layer was washed with water (50 ml), brine (50 ml)
7. dry with materialdried (MgSO4)
8. concentrationconcentrated
9. customThe product was purified by flash silica column chromatography (ethyl acetate:Hexane 1: 4)

ORD record

ord-64bd5caa6b434cbcbf240fa7a9f912c8

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09173938B2