The Phenolic Ether Group used for Protective Purposes

13 The Phenolic Ether Group used for Protective Purposes 

The dimethoxy trityl group at the 5-position in the derivative shown was removed preferentially by addition of the compound to a suspension of zinc bromide in nitromethane and work-up after 1 minute to afford a quantitative yield (ref. 186). 

The 4-methoxybenzyl ether group in the compound shown was preferentially removed in dichloromethane solution containing anisole and stannous chloride upon treatment at ambient temperature with trimethylchlorosilane during 30 minutes to give the product in 87% yield (ref. 187). 

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