Regioselective and Site-Selective Syntheses of Oxetanes

The following sections describe the regioselective, site-selective, and stereoselective synthesis of oxetanes. 

the bicyclic oxetane 0X2 was found to be selectively formed in the PB reaction of 2-methyl-, 2,3-dimethyl-, 2-hydroxymethyl-, and 3-methylfuran. However, in the PB reaction of 2,4-dimethylfuran (R1 = H, R2 = H, R3 = CH3, R4 = H), a 1 1 mixture of the oxetanes 0X1 and 0X2 was observed under the similar photochemical reaction conditions. 

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