Hydrochloric Acid → Pyroquilon

A solution of 3-chloropropanoyl chloride (9.1 ml, 95.0 mmol) in 20 ml dry acetone was added dropwise to a solution of indoline (20.5 g, 0.21 mol) in 80 ml dry acetone and the mixture was refluxed for 1 h. After cooling to ambient temperature the solution was poured into 500 ml stirred 2N HCl and extracted with ethyl acetate (3×150 ml). After washing with 1N HCl and brine and drying over MgSO4 the solvent was removed under reduced pressure and the crude product was obtained as a pale yellow solid. This was added portionwise to a molten mixture of AlCl3 (60.0 g, 0.45 mol) and NaCl (17.5 g, 300 mmol) at 150° C. and stirred for additional 30 min. On cooling, excess aluminum chloride was decomposed by the addition of a chilled mixture of 20 ml concentrated hydrochloric acid and 500 ml water. Extraction with ethyl acetate (3×200 ml), followed by drying over MgSO4 and removal of the solvent gave a yellow solid, which was purified by crystallization from acetone/ether yielding 1,2,5,6-tetrahydro-pyrrolo[3,2,1-ij]quinolin-4-one (11.8 g, 65.8 mmol, 69%) as colorless needles.

1. temperaturethe mixture was refluxed for 1 h
2. additionwas poured into 500 ml
3. extractionextracted with ethyl acetate (3×150 ml)
4. washAfter washing with 1N HCl and brine
5. dry with materialdrying over MgSO4 the solvent
6. customwas removed under reduced pressure
7. customthe crude product was obtained as a pale yellow solid
8. temperatureOn cooling
9. extractionExtraction with ethyl acetate (3×200 ml)
10. dry with materialby drying over MgSO4 and removal of the solvent
11. customgave a yellow solid, which
12. customwas purified by crystallization from acetone/ether

ORDレコード

ord-ee237da8205243208de063c1c1dd0743

出典データセット

uspto-grants-2013_09

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US08541404B2