2‑Naphthylmethoxymethyl as a Mildly Introducible and Oxidatively Removable Benzyloxymethyl-Type Protecting Group

Abstract

2-Naphthylmethoxymethyl (NAPOM) was developed for the protection of various hydroxy (including phenolic hydroxy and carboxy) and mercapto groups. The NAPOM group can be introduced in extremely mild conditions (naphthyl­methoxy­methyl chloride, 2,6-lutidine, room temperature) without concomitant acyl migration in a 1,2-diol system. Furthermore, selective removal of NAPOM in the presence of naphthylmethyl (NAP) and <i>p</i>-methoxybenzyl (PMB) groups and, conversely, that of PMB in the presence of NAPOM were realized. These results, as well as its easy handling and compatibility with various solvents, show that NAPOM is a novel and useful choice as a protecting group