Water → 3-Ethylbicyclo[3.2.0]hept-3-en-6-one

(2E)-4-Ethylhepta-2,6-dienoic acid (100.57 g) obtained by the method described above was dissolved in N,N-dimethylacetamide (255 mL) under a nitrogen atmosphere. To the solution, acetic anhydride (108 mL, 1.14 mol) and triethylamine (79 mL, 0.57 mol) were added. The reaction mixture was warmed and stirred at 115 to 117° C. for 5 hours. The reaction mixture was cooled to room temperature, and n-hexane (510 mL) and water (714 mL) were added thereto to separate an organic layer. The aqueous layer was subjected to two extractions with hexane (each with 255 mL), and all the organic layers were combined and then washed with a 5% aqueous sodium bicarbonate solution (102 mL) and water (102 mL) in this order. The obtained organic layer was concentrated under reduced pressure, and the residue was distilled (90-100° C., approximately 25 mmHg) to obtain the title compound (50.92 g, colorless oil substance) (overall yield from 1,1-bis(allyloxy)butane: 62%).

1. temperatureThe reaction mixture was warmed
2. temperatureThe reaction mixture was cooled to room temperature
3. customto separate an organic layer
4. extractionThe aqueous layer was subjected to two extractions with hexane (each with 255 mL), and all the organic layers
5. washwashed with a 5% aqueous sodium bicarbonate solution (102 mL) and water (102 mL) in this order
6. concentrationThe obtained organic layer was concentrated under reduced pressure
7. distillationthe residue was distilled (90-100° C., approximately 25 mmHg)

ORD record

ord-38c165ef04824a118e4da833deecbd15

Source dataset

uspto-grants-2015_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09162971B2