Metal-catalyzed functionalization of alkynes and poly(2,6-dimethyl-1, 4-phenylene oxide)

Abstract

The development of new synthetic methods for modification of existing organic compounds and polymers is of scientific and industrial interest. This thesis consists of two parts: 1) A new facile method to selectively oxidize alkynes to the corresponding acetylenic ketones, 2) Chemical modification of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) to the corresponding PPO with acetoxy pendant group, respectively. In the first part of thesis, a facile catalytic system using inexpensive metal ions to selectively oxidize alkynes to the corresponding acetylenic ketones under mild conditions with be described. 4-octyne, a model substrate, has been oxidized to the 4-ocytn-3-one by using CuCl2/t-BuOOH/O2 in the presence of t-butyl alcohol. Optimal reaction conditions including the variations of metal catalysts, catalyst and oxidant concentrations as well as addition methods have been determined systemically. Moreover, the versatility of this catalytic system on symmetrical, unsymmetrical, terminal and functionalized alkynes has also been studied. In the second part of the thesis, chemical modification of PPO to the corresponding PPO with acetoxy pendant group by cobalt(III) acetate in a mixture of chloroform and acetic acid under nitrogen was investigated. Reaction variables such as temperature, stirring method, ratio of solvent and cobalt(III) concentration have been examined. Reaction kinetic was also investigated. Chemical structures of the modified PPO were characterized by FTIR, 1H-NMR, and their physical properties were studied by intrinsic viscosity, GPC and DSC. Finally, the reaction mechanism was proposed which involved an electron transfer reaction and cobalt-induced degradation of PPO.