Progress is reported on the cleavage of bonds in coal and coal analogs. This quarter, 9-Phenylthioanthracene (9-PTA) was chosen as an appropriate substrate to test the hypothesis that reductive cleavage of bonds to aromatic rings caused by heating in hydrogen donor solvents, such as tetralin, may be catalyzed by electron donating agents in the absence of hydrogen bonding or acidic reagents. Ca. 0.02 M solutions of 9-PTA in tetralin (purified by chromatography on neutral alumina) were heated in glass ampoules. It was observed that decomposition of 9-PTA occurs on heating at temperatures as low as 250{degree}C, even in the absence of additives or catalysts. Reductive cleavage (measured by yields of anthracene), however, was invariably a minor process. Two major products, obtained at retention times of ca. 6.5 and 9.0 min., respectively, were observed in all runs. However, these products were obtained in rather variable yields, with an increase in the yield of one product often being accompanied by a decrease in the yield of the other. The nature of the products is unknown. GC-MS analysis is awaited. Addition of 2,6-xylenol, 1,3,5-trimethoxybenzene, or 1,4-dimethoxynaphthalene to the thermolysis mixtures appeared to offer, at best, only slight increases in reaction rates, and little change in product compositions.
