Cyclic dimers (1) and trimers (2) of 1, 2-diethynyilbenzenes (3) were prepared by multi-step synthesis, from diiodoarenes (4) via 1, 2-diethynyilbenzenes and oxidative coupling. According to our knowledge, this is the first example of Eglinton-Galbraith dimer derivatives with electron acceptor groups. These compounds can be produced in useful quantities and are of interest as precursors to novel conjugated organic polymers [1, 2]. Spectroscopic data obtained by measurements of dehydrobenzoannulenes with electron acceptor groups are compared with the same compounds containing electron donor groups. To better understand 1, an X-ray crystal structure analysis of R=COOC10H21 derivative was performed. This dimer undergoes a rapid and very exothermic polymerization at 70-90 oC. The identification and thermal behaviour of 1 and 2 will be discussed. 1. Q. Zhou, P.J. Carroll. T.M. Swager ; J. Org. Chem. 1994, 59, 1294 2. J.J. Pak, T.J.R. Weakley, M.M. Haley ; J. Am. Chem. Soc. 1999, 121, 8182

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