Five- and Six-membered-ring Compounds

Certain cyclic ethers which will not homopolymerize will copolymerize with THF (25, 52). These cyclic ethers are stable five and six-membered ring compounds such as 2-methyltetrahydrofuran (2-MeTHF), and 1,4-dioxane (DOX). It is probable that 4-phenyl-l,3-dioxane (PhDOX), tetrahydropyran (THP), and 4-methyl-l,3-dioxolane (MDOL) which do not homopolymerize but which have been reported to copolymerize with BCMO (107, 108) would also copolymerize with THF. In the copolymerizations a correlation was again found between the basicity of the attacking ether and its reactivity with the cyclic oxonium ion. The... 

A number of formal [2 + 3] and [2 + 4] cycloadditions of disilenes giving five- and six-membered ring compounds have been discussed in review OW, while their mechanisms have not been elucidated in detail. 

The Dieckmann reaction is of major importance for the synthesis of five- and six-membered ring compounds. The present account will review the earlier work where necessary, but will concentrate on important developments since the review in Organic Reactions. ... 

Systematic investigations of the mass spectrometric fragmentation of heteroaromatic A-imines show a difference between the behavior of five-and six-membered ring compounds. 

This chapter will present the most fundamental concepts for structure, nomenclature, and chemical reactions of simple heterocyclic compounds. The primary focus is on five- and six-membered ring compounds that contain one or two oxygen, nitrogen, of sulfur atoms. Simple bicyclic heterocyclic compounds will also be introduced. The chemical reactions for generating the heterocycles as well as the fundamental chemical reactions will be seen as relatively simple extensions of chemistry presented elsewhere in this book. 

Lebreux F, Buzzo F, Marko IE (2008) Synthesis of five- and six-membered-ring compounds by environmentally friendly radical cyciizations using koibe electrolysis. Syniett 2815-2820 Sato N, Sekine T, Sugino K (1968) Anodic processes of acetate ion in methanol and glacial acetic acid at various anode materials. J Electrochem Soc 115 242-246... 

Ru-catalyzed RCM reactions exerted their efficiency not only on the formation of five- and six-membered ring compounds as illustrated in Table 24.1, Schemes 24.2 and 24.3,... 

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