Pyridinium chloride → 5-Hydroxy-2-methylbenzaldehyde

Temperature

170 °C

A stirred mixture of 5-methoxy-2-methylbenzaldehyde (24.9 g) and pyridine hydrochloride (100 g) is heated at 170° C. for 7 hours. Water (250 mL) is added cautiously to the reaction mixture at 140° C. and the very dark mixture is extracted twice with chloroform (250 mL), filtration through hyflo removes a small amount of insoluble black solid and aids separation. The organic phase is washed with 1 N hydrochloric acid (250 mL), with water (250 mL), with brine (250 mL), dried over magnesium sulphate and evaporated. The residue is washed with pentane to give 5-hydroxy-2-methylbenzaldehyde (10.66 g) as a cream solid, m.p. 116-118° C.

1. extractionthe very dark mixture is extracted twice with chloroform (250 mL), filtration through hyflo
2. customremoves
3. customa small amount of insoluble black solid and aids separation
4. washThe organic phase is washed with 1 N hydrochloric acid (250 mL), with water (250 mL), with brine (250 mL)
5. dry with materialdried over magnesium sulphate
6. customevaporated
7. washThe residue is washed with pentane

ORD record

ord-1126fac1f97949c8904d83d3b1d70880

Source dataset

uspto-grants-2001_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06211234B1