An Efficient Means for Generating p-Methoxybenzyl (PMB) Ethers under Mildly Acidic Conditions

Abstract

The protection of a wide variety of alcohols as their p-methoxybenzyl ethers can be performed with PMBO-lepidine in the presence of methyl tosylate or, preferably, camphorsulfonic acid. No inorganic promoters are required, thereby facilitating workup and product isolation.

Key words

p-methoxybenzyl ethers - protecting groups - camphorsulfonic acid - lepidine derivatives - methyl tosylate

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