tert-Butyl hydroperoxide → HCID 178495889, compound

Participants

Reaction Steps

To a solution of the above thiohydantoin (4.47 g, 9.95 mmol) and aminoacetaldehyde dimethylacetal (6.50 mL, 59.7 mmol) in 20 mL of MeOH was added 7.69 mL (59.7 mmol, 70% in water) of t-butyl hydroperoxide solution, dropwise over 25 min. During the addition and for about 1 h after, the internal temperature of the mixture was kept below 20° C. with an ice water bath. The mixture was stirred at room temperature for 86 h, and 25 mL of saturated NaHSO3 solution was added slowly dropwise, maintaining the internal temperature below 20° C. with an ice water bath. The resulting cloudy white mixture was concentrated. To the residue was added EtOAc, and this mixture was concentrated again. The oily residue was partitioned between EtOAc and water, and the aqueous phase was separated and extracted with EtOAc. The combined organic layers were washed with water and brine, dried over Na2SO4, filtered and concentrated to give 5.21 g of (R)-3-(3,5-dichloro-phenyl)-2-[(E)-2,2-dimethoxy-ethylimino]-5-methyl-5-(4-trifluoromethoxy-benzyl)-imidazolidin-4-one as a thick yellow oil.

Provenance & Evidence