2,3-Dimethyl-2-butene → 2-Azetidinone, 3,3,4,4-tetramethyl-

To a solution of 2,3-dimethyl-2-butene (5.76 g) in toluene (46.0 mL), chlorosulfonyl isocyanate (5.91 mL) was added at 0° C. After being stirred at that temperature for 10 minutes, the mixture was brought to room temperature. After being stirred for 45 minutes, the mixture was diluted with added toluene (69.0 mL). To a mixture of a solution of 25% sodium hydroxide in water (49.1 mL) and benzyltriethylammonium chloride (99.0 mg), the reaction mixture was added over a period of one hour. The resulting mixture was added dropwise to a solution of 25% sodium hydroxide in water and the mixture was stirred at 50° C. for an hour. After being cooled to room temperature, the mixture was extracted with toluene twice. The combined organic layers were washed with saturated brine and dried over added anhydrous magnesium sulfate. The desiccant was removed by filtration and the filtrate was concentrated under reduced pressure. The resulting residue was recrystallized with toluene to give 3,3,4,4-tetramethylazetidine-2-one as a colorless solid (5.52 g).

1. customwas brought to room temperature
2. stirringAfter being stirred for 45 minutes
3. additionthe reaction mixture was added over a period of one hour
4. stirringthe mixture was stirred at 50° C. for an hour
5. extractionthe mixture was extracted with toluene twice
6. washThe combined organic layers were washed with saturated brine
7. customdried
8. additionover added anhydrous magnesium sulfate
9. customThe desiccant was removed by filtration
10. concentrationthe filtrate was concentrated under reduced pressure
11. customThe resulting residue was recrystallized with toluene

ORD record

ord-851444985498466b8185860d23d36f20

Source dataset

uspto-grants-2016_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09422240B2