p-Toluenesulfonic acid → HCID 71059330, compound

(R)-3-(4-Bromophenoxy)-2-methylpropane-1,2-diol (25 g, 0.1 mol) and p-toluenesulfonic acid (0.91 g, 4.8 mmol) were dissolved in acetone (300 g), followed by stirring under reflux for 5.5 hours. The progress of reaction was monitored by TLC. The generated water was removed by azeotropic distillation with 300 g of solvent under atmospheric pressure, and 300 g of acetone was added during the reaction. After the reaction was completed, the solvent was removed under a reduced pressure and the resulting concentrated residue was dissolved in isopropyl acetate (250 mL). The organic layer thus obtained was washed with a 1 M sodium hydroxide aqueous solution (100 mL). Thereafter, the organic layer was concentrated and dried, obtaining 25 g of (S)-4-(4-bromophenoxy)methyl-2,2,4-trimethyl-1,3-dioxolane (yield: 82%).

1. temperatureunder reflux for 5.5 hours
2. customThe progress of reaction
3. customThe generated water was removed by azeotropic distillation with 300 g of solvent under atmospheric pressure, and 300 g of acetone
4. additionwas added during the reaction
5. customthe solvent was removed under a reduced pressure
6. dissolutionthe resulting concentrated residue was dissolved in isopropyl acetate (250 mL)
7. customThe organic layer thus obtained
8. washwas washed with a 1 M sodium hydroxide aqueous solution (100 mL)
9. concentrationThereafter, the organic layer was concentrated
10. customdried

ORD record

ord-bfdb780b1ccb4e8285cfd6e450340b40

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08598358B2