Cleavage of Benzylidene Acetal with PMA/SiO₂

Significance

Phosphomolybdic acid supported on silica gel (PMA/SiO₂) catalyzed the cleavage of benzylidene acetals at room temperature to give the corresponding diols in 75-97% yield (20 examples, equation 1). PMA/SiO₂ was also applied to the deacetalization of N-protected 2-phenyl-1,3-oxazolidines (88-95% yield, 5 examples, equation 2). The catalyst was recovered by simple filtration and reused three times without significant loss of catalytic activity.