SHUNJI SAKAMOTO
Specialty Chemicals Division, ZEON CORPORATION, 1-6-2 Marunouchi, Chiyoda-ku, Tokyo, 1008246, Japan

Abstract

Cyclopentyl methyl ether (CPME) is an alternative solvent and has preferable properties including higher hydrophobicity, lower formation of peroxides and better stability under acidic and basic conditions compared to other traditional ether solvents such as tetrahydrofuran.
Due to the above unique properties, CPME has particular advantages and renders some conventional reaction sequences in one pot or easier process as a result of solvent unification and facile isolation of the products, which contribute to Green Chemistry as well as to process innovation.
CPME meets eight definitions out of the 12 Principles of Green Chemistry (1) because of the above characteristics as well as its manufacturing process and its applications.

INTRODUCTION

In the recent process chemistry for pharmaceutical and other fine chemical industries, scientists’ demand for greener solvents has been increasing day by day. In view of the circumstances, typical ether solvents, such as tetrahydrofuran (THF), 2-methyl tetrahydrofuran (MeTHF), Diisopropylether (IPE), 1,4-dioxane and methyl t-butyl ether (MTBE), have some inherent properties which are incompatible with Green Chemistry. For example, THF easily forms explosive peroxides (2) and is difficult to recover because of its infinite miscibility with water. MeTHF is the unrivaled replacement for THF because of its high solvency and low miscibility with water as well as renewability (3). However, it generates more peroxides than THF (Figure 1) and is still soluble in water at 14 wt% (20°C) (3).
In November, 2005, Cyclopentyl methyl ether (CPME) was commercialized by ZEON CORPORATION with its unique C5 feedstock and synthetic technologies. CPME has been found to be an alternative solvent and has many preferable characteristics for Green Chemistry. Because it is free of drawbacks including easy peroxide formation and water miscibility, the deman ...