Dimethyl Sulfoxide → p-Chlorocinnamaldehyde

Temperature

-70 °C

A solution of oxalyl chloride (2.6 mL, 30 mmol) in methylene chloride was cooled to −70° C. in a dry ice/acetone bath and DMSO (4.2 mL, 60 mmol) was added slowly. After 10 minutes, a solution of 4-chlorocinnamyl alcohol (2.0 g, 12 mmol) from Step A in methylene chloride (12 mL) was added. The reaction was stirred at −70° C. for 80 min and then DIPEA (20 mL, 120 mmol) was added. After 5 min, the reaction was allowed to warm to rt over 2 h. The mixture was diluted with methylene chloride and washed with cold 2N hydrochloric acid (80 mL). The organic layer was washed with brine containing some aq. sodium bicarbonate, dried over sodium sulfate, and evaporated. The residue was purified by FC (0 to 10% ethyl acetate in hexanes) to give the title compound as a white solid. 1HNMR (CDCl3): δ 6.71 (dd, J=7.7 and 16.0 Hz, 1H), 7.450 (d, J=16 Hz, 1H), 7.43 and 7.52 (Abq, J=8.4 Hz, 4H), 9.72 (d, J=7.6 Hz, 1H).

1. waitAfter 5 min
2. temperatureto warm to rt over 2 h
3. washwashed with cold 2N hydrochloric acid (80 mL)
4. washThe organic layer was washed with brine containing some aq. sodium bicarbonate
5. dry with materialdried over sodium sulfate
6. customevaporated
7. customThe residue was purified by FC (0 to 10% ethyl acetate in hexanes)

ORD record

ord-348ac1d116fc45b5a51d01f1a7c4564e

Source dataset

uspto-grants-2007_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07271266B2