Oxygen → 5-t-Butyl-1-(4-hydroxy-2-phenylbenzo[d]oxazol-6-yl)-4,4-dimethyl-2,6,7-trioxabicyclo[3.2.0]heptane

Participants

Reaction Steps

To 15 mL of methylene chloride were added 1.0 mg of TPP and 156 mg (0.43 mmol) of 4-t-butyl-5-(4-hydroxy-2-phenylbenzo[d]oxazol-6-yl)-3,3-dimethyl-2,3-dihydrofuran (Compound [63]), and the mixture was externally irradiated with a 940 W sodium lamp in an oxygen atmosphere for 30 minutes, then concentrated. The concentrate was applied to a silica gel column and the elution was carried out with the mixture of hexane and ethyl acetate (hexane:ether =1:1) to obtain 25.3 mg of 5-t-butyl-1-(4-hydroxy-2-phenylbenzo[d]oxazol-6-yl)-4,4-dimethyl-2,6,7-trioxabicyclo[3.2.0]heptane (Compound [64]) as colorless granular crystal. Yield 85.1%.

Provenance & Evidence