REACTIVITIES OF STABLE ROTAMERS .38. REACTION OF CHLORINE WITH 1-(9-FLUORENYL)-2-(1-METHYLETHENYL)NAPHTHALENE ROTAMERS - OUTSTANDING SOLVENT EFFECTS ON PRODUCT DISTRIBUTION AND RITTER TYPE REACTIONS IN ACETONITRILE

Reactions of the olefinic moiety of the title compounds with chlorine were done as carbon tetrachloride, nitromethane, and acetonitrile solu tions. The ap-isomer afforded a mixture of the corresponding addition product and olefins that are derived by deprotonation of the interveni ng chloro-carbocation. The product distribution was strongly affected by the solvents, although chlorinated olefins are the main products in carbon tetrachloride. The sp-isomer yielded the chloro-olefins that a re rotationally isomeric with these compounds in carbon tetrachloride. No cyclized compound, which is expected if the attack of the intermed iate cation on a benzene ring closely located to it takes place, was d etected under these conditions. By contrast, the reaction in nitrometh ane resulted in formation of the cyclized compound as a major product from the sp isomer. In acetonitrile, the reaction afforded the cyclize d compound in a fair yield from the sp, but that of the ap isomer gave products that were derived by the Ritter type reactions, in addition to those observed in other solvents. The results are attributed to the stability of the intervening cations in these solvents. In the Ritter type reaction, the first evidence that deprotonation from the interve ning acetonitrilium ion to produce a ketene imine was obtained. The br omine addition to the olefinic bond in the sp-isomer of the title comp ound revealed that the solvent seriously affects the yields of the cyc lic compound as well as the ratios of two bromo-olefins.