PREPARATION OF ETHERS AND EPOXIDES

Kitamura. T. Zheng, L. Taniguchi, H. Sakurai, M. Tanaka, R. Tetrahedron Lett., 1993, 34, 4055 

ETHERS, EPOXIDES AND THIOETHERS FROM ACID DERIVATIVES 

Garavelas, A. Mavropoulos, I. Perlmutter. P. Westman, G. Tetrahedron Lett, 1995, 36,463 

Hatakevama. S. Mori, H. Kitano, K. Yamada, H. Nishizawa. M. Tetrahedron Lett., 1994, 35, 4367 

SECTION 129 ETHERS, EPOXIDES AND THIOETHERS FROM ETHERS, EPOXIDES AND THIOETHERS 

Yuncbeng, Y. Yulin, J. Jun, P. Xiaohui, Z. Conggui, Y. Gazz- Chinu Ital, 1993, 123, 519 

Bhckvall, J.-E. Andersson. P.G. Tetrahedron Lett., 1995, 36, 7749 BnBr, CS2CO3, MeCN 

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A one-pot process to displace the halogen end groups by allyl end groups was developed using allyl tri-n-butyltin. The reaction of an alkyl halide with allyl tri-n-butyltin is a radical reaction that tolerates the presence of other functional groups such as acetals, ethers, epoxides, and hydroxyl groups. This technique was also used for the deshalogenation of polymers prepared by ATRP (Scheme 19). 

Epoxides - Organic compounds containing three-membered cyclic group(s) in which two carbon atoms are linked with an oxygen atom as in an ether. This group is called an epoxy group and is quite reactive, allowing the use of epoxides as intermediates in preparation of certain fluorocarbons and cellulose derivatives and as monomers in preparation of epoxy resins. 

It does not homopolymerize easily and hence can be stored as a liquid. It undergoes many addition reactions typical of an olefin. Reactions inclnde preparation of linear dimers and trimers and cyclic dimers (21,22) decomposition at 600°C with subsequent formation of octafluoro-2-butene and octafluoroisobutylene (23) oxidation with formation of an epoxide (24), an intermediate for a number of perflu-oroalkyl perfluorovinyl ethers (25,26) and homopolymerization to low molecular weight liquids (27,28) and high molecular weight solids (29,30). Hexafluoropropylene reacts with hydrogen (31), alcohols (32), ammonia (33), and the halogens and their acids, except I2 and HI (31,34-36). It is used as a comonomer to produce elastomers and other copolymers (37-41). The toxicological properties are discussed in Reference 42. 

Introduction to Ethers Nomenclature of Ethers Structure and Properties of Ethers Crown Ethers Preparation of Ethers Reactions of Ethers Nomenclature of Epoxides Preparation of Epoxides Enantioselective Epoxidation Ring-Opening Reactions of Epoxides Thiols and Sulfides... 

One of the most commonly used groups of epoxide resins is that comprised of the diglycidyl ethers, and these are made by reacting epichlorohydrin with a bisphenol such as bisphenol A. The preparation of the diglycidyl ether of bisphenol A has already been illustrated, but many other glycidyl ether type epoxides are of considerable importance. The preparation of an epoxide novolac type resin is shown below ... 

Some of the methods listed in section 132 (Ethers and Epoxides from Ketones) may also be applied to the preparation of ethers and epoxides from aldehydes... 

No examples of the preparation of ethers and epoxides by replacement of alkyl, methylene and aryl groups occur in the literature. For the conversion RH —ROR (R=alkyl, aryl etc.) see section 131 (Ethers from Hydrides)... 

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