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

Participants

Reaction Steps

Adding 1 mg of TPP and 27.9 mg (0.058 mmol) of 4-t-butyl-5-[4-(t-butyldimethylsiloxy)-2-phenylbenzo[d]oxazol-6-yl]-3,3-dimethyl-2,3-dihydrofuran (Compound [65]) to 5 ml of methylene chloride, the mixture was externally irritated with a 940 W sodium lamp for 30 minutes in oxygen atmosphere. After concentrated, the resulting mixture was applied to a silica gel column and the elution was carried out the mixture of hexane and ethyl acetate (hexane:ethyl acetate=15:1) to obtain 25.3 mg of 5-t-butyl-1-[4-(t-butyldimethylsiloxy)-2-phenylbenzo[d]oxazol-6-yl]-4,4-dimethyl-2,6,7-trioxabicyclo[3.2.0]heptane (Compound [66]) as a purple oil. Yield 85.1%.

Provenance & Evidence