Phosphate → Azetidon

In 300 ml of acetone were dissolved 3 g (7.5 mmole) of the product containing as a main component (3R, 4R)-4-acetoxy-3-[(R)-1-t-butyldimethylsilyloxyethyl]-1-(1-methoxycarbonyl-2-methylprop-1-enyl)azetidin-2-one, which had been obtained in Preparation 5. To the solution was added a solution of 6.43 g (30.1 mmole) of sodium metaperiodate and 120 mg of potassium permanganate in a mixture of 150 ml of water and 150 ml of a 0.1 M phosphate buffer solution (pH 7.02) at about 18° C. over 30 minutes, and then the mixture was stirred at that temperature for 4 hours. After completion of the reaction, the precipitate produced was filtered off and about 25 ml of the above buffer solution was added to the filtrate to adjust its pH to a value of 6.8. The acetone was distilled off at a lower temperature under reduced pressure and the residue was extracted with benzene. The benzene layers were collected and dried. The solvent was distilled off to give a crystalline solid, which was recrystallized from hexane to afford 0.934 g (43.3%) of the desired product as needles melting at 104°-106° C.

1. customhad been obtained in Preparation 5
2. customAfter completion of the reaction
3. customthe precipitate produced
4. filtrationwas filtered off
5. additionabout 25 ml of the above buffer solution was added to the filtrate
6. distillationThe acetone was distilled off at a lower temperature under reduced pressure
7. extractionthe residue was extracted with benzene
8. customThe benzene layers were collected
9. customdried
10. distillationThe solvent was distilled off
11. customto give a crystalline solid, which
12. customwas recrystallized from hexane

ORD record

ord-5f37e92a80ee4fbda25bc0f39a91a810

Source dataset

uspto-grants-1983_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04395418