The 4-methoxybenzyl (MPM) protectinggroup for hydroxy functions is readily removed with DDQ in dichloromethane containing a small amount of water at room temperature. Under these neutral conditions, several other protecting and functional groups remained unchanged. 3,4-Dimethoxybenzyl (DMPM) groups are more reactive than MPM groups with DDQ. The benzyl (Bn) protectinggroup was removed by catalytic
Selective hydrogenolysis of the benzyl protecting group for hydroxy function with raney nickel in the presence of the MPM (4-methoxybenzyl) and DMPM (3,4-dimethoxybenzyl) protecting groups
The benzyl protectinggroup for hydroxy function was selectively removed by catalytic hydrogenolysis with Raney nickel in the presence of the MPM (4-methoxybenzyl) and DMPM (3,4-dimethoxybenzyl) protectinggroups, and applied to the synthesis of some synthons to macrolide and polyether antibiotics.