4-Chlorobenzaldehyde → HCID 20242542, compound

Temperature

100 °C

A flask containing polyphosphoric ester (90 g) was held at 100° C. (oil bath temperature). A mixture of 3,4-methylenedioxyphenylacetamide (22 g, 123 mmol) and parachlorobenzaldehyde (17.1 g, 122 mmol) was added in three portions over half an hour, with stirring. The solution (dark red) was heated at 100° C. for 5 h and poured onto ice (400 ml). A 10% solution (aqueous) of sodium carbonate (2 liters) was added and the mixture was left overnight. The resulting oily gum was extracted with chloroform (2×500 ml) and the chloroform extracts washed with brine (50 ml) and dried over sodium sulphate. The chloroform solution was filtered and the solvent was removed under reduced pressure. The solid so formed was triturated with ethanol (2×30 ml) to give 1-(4-chlorophenyl)-6,7-methylenedioxy-1,4-dihydroisoquinol-3-one (7 g). The combined ethanol layers were evaporated under reduced pressure and the residue chromatographed (Silica gel (300 g), chloroform as eluent) to give a further 8 g of product. Total yield (15 g, 41%), m.p. 200°-202° C. (ethanol).

1. customwas held at 100° C.
2. additionwas added in three portions over half an hour
3. additionpoured onto ice (400 ml)
4. extractionThe resulting oily gum was extracted with chloroform (2×500 ml)
5. washthe chloroform extracts washed with brine (50 ml)
6. dry with materialdried over sodium sulphate
7. filtrationThe chloroform solution was filtered
8. customthe solvent was removed under reduced pressure
9. customThe solid so formed
10. customwas triturated with ethanol (2×30 ml)

ORD record

ord-37fc86c1dbf44a6aae4c8f9db5852645

Source dataset

uspto-grants-1986_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04578393