Methanol → 3-nitro-5-oxo-6,7,8,9-tetrahydro [5H] benzocycloheptene-7-carbonitrile

Temperatur

90 °C

A mixture of 50 g of 3-nitro-8,9-dihydro [5H] benzocycloheptene-5-one, 1200 ml of methanol, 120 ml of tetrahydrofuran, 100 ml of a 10% aqueous potassium carbonate and 50 ml of acetone cyanhydrin under nitrogen was refluxed for an hour in a bath at 90° C. and the mixture was concentrated to about 200 ml under reduced pressure. The mixture was cooled to 20° C. and was extracted with methylene chloride. The organic phase was washed with water, dried and distilled to dryness under reduced pressure. The 58 g of brown oil residue were crystallized from 50 ml of methanol and the mixture was vacuum filtered to obtain 46 g of 3-nitro-5-oxo-6,7,8,9-tetrahydro [5H] benzocycloheptene-7-carbonitrile with a melting point of 107° C. and then 120° C.

1. concentrationthe mixture was concentrated to about 200 ml under reduced pressure
2. temperatureThe mixture was cooled to 20° C.
3. extractionwas extracted with methylene chloride
4. washThe organic phase was washed with water
5. customdried
6. distillationdistilled to dryness under reduced pressure
7. customThe 58 g of brown oil residue were crystallized from 50 ml of methanol
8. filtrationfiltered

ORD-Eintrag

ord-2b0346b56d1d41af8c8e1dd4e1b2dc2c

Quelldatensatz

uspto-grants-1978_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04117164