Hydrochloric Acid → 4-Hydroxy-6,6-dimethyl-3-oxabicyclo[3.1.0]hexan-2-one

Temperature

0 °C

0.25 ml of a solution of 2M butyllithium in cyclohexane was added at -20° C. to 0.55 ml of a molar solution of diisopropylamine in tetrahydrofuran and 5 ml of tetrahydrofuran and the temperature was allowed to rise to 0° C. and was then cooled to -60° to -70° C. 180 mg of the product of Step B were added all at once to the mixture at -60° to -70° C. and the mixture was heated over 2 hours at 0° C. The mixture was held at 0° C. for one hour and was poured into 2N hydrochloric acid. The mixture was stirred for 17 hours at 20° C. and the decanted aqueous phase was extracted with chloroform. The organic phase was dried and evaporated to dryness and the residue was taken up in a mixture of isopropyl ether and petroleum ether. The solution was extracted with water and the aqueous extract was evaporated to dryness under reduced pressure to obtain 30 mg of crystalline dl 6,6-dimethyl-4-hydroxy-3-oxabicyclo-[3,1,0]-hexan-2-one melting at 80° C.

1. customto rise to 0° C.
2. temperaturewas then cooled to -60° to -70° C
3. extractionthe decanted aqueous phase was extracted with chloroform
4. customThe organic phase was dried
5. customevaporated to dryness
6. additionthe residue was taken up in a mixture of isopropyl ether and petroleum ether
7. extractionThe solution was extracted with water
8. extractionthe aqueous extract
9. customwas evaporated to dryness under reduced pressure

ORD record

ord-fed9271e2f4846859138658b09086ec9

Source dataset

uspto-grants-1985_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04556732