Three-Component Polycondensation of Bis(diazoketone) with Dicarboxylic Acids and Cyclic Ethers: Synthesis of New Types of Poly(ester ether ketone)s
journal contributionposted on 09.08.2011, 00:00 by Eiji Ihara, Yuji Hara, Tomomichi Itoh, Kenzo Inoue
New types of poly(ester ether ketone)s 3 and 8 were prepared by three-component polycondensation of bis(diazoketone) 1 with a variety of dicarboxylic acids 2 and THF or THP catalyzed by Rh2(OAc)4. THF was ring-opened and incorporated into almost every carboxyl O–H of 2 via simultaneous insertion together with a diazocarbonyl-derived carbene, resulting in the formation of a unique poly(ester ether ketone) framework. On the other hand, when THP was used as a cyclic ether, insertion of carbene alone into the carboxyl O–H (normal insertion) competes with the simultaneous insertion of THP and carbene, and the ratio of the two modes of insertion depends on the kind of 2 employed. The mode and selectivity of the propagation were confirmed by conducting Rh-catalyzed model reactions of diazoacetophenone 4 with 4-tert-butylbenzoic acid 5 in THF and THP.