Potassium bisulfate → 2-(3-chlorophenyl)acetaldehyde

A suspension of LiAIH4 (1.90 g, 51 mmol) in anhydrous ether (250 mL) was stirred at room temperature tinder nitrogen for about 1 hour. The suspension was cooled to about 45° C. To it was added drops of a solution of 2-(3-chlorophenyl)-N-methoxy-N-methyl-acetamide (8.19 9, 38.3 mmol, see Preparation 1) in 10 mL of anhydrous tetrahydrofuran (THF). The mixture was warmed to about 0° C. and stirred for about 3 hours. The solution was then cooled to about 45° C. To this solution was slowly added a solution of KHSO4 (13 g) in water (about 30 mL) the resulting mixture was filtered through CELITE®. The filtrate was concentrated in vacuo, the resulting solution was diluted with DCM and washed with 1N HCl aqueous solution (2 times), and brine (2 times) dried over anhydrous MgSO4, filtered and concentrated in vacuo. The title compound was obtained as a liquid (5.80 g), which was used immediately in the next step without further purification. Rf=0.71 (silica, EtOAc/hexane 1:3).

1. temperatureThe suspension was cooled to about 45° C
2. temperatureThe mixture was warmed to about 0° C.
3. stirringstirred for about 3 hours
4. temperatureThe solution was then cooled to about 45° C
5. filtrationwas filtered through CELITE®
6. concentrationThe filtrate was concentrated in vacuo
7. additionthe resulting solution was diluted with DCM
8. washwashed with 1N HCl aqueous solution (2 times), and brine (2 times)
9. dry with materialdried over anhydrous MgSO4
10. filtrationfiltered
11. concentrationconcentrated in vacuo

ORD record

ord-e1eab1cefddf43639d6b24089cce3cb9

Source dataset

uspto-grants-2002_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06420555B1