SYNTHESIS OF SUBSTITUTED FLUORENONES AND SUBSTITUTED 3',3'-DICHLOROSPIRO[FLUORENE-9,2'-THIIRANES] AND THEIR REACTIVES

Several novel 9-fluorenones were synthesized and were used as precurso rs in an attempt to prepare unique substituted 3',3'-dichlorospiro[flu orene-9,2'-thiiranes]. Several of the thiiranes were unstable and desu lfurized during their preparation (7a-d,11,12). ichloro(2,5-dimethoxys piro[fluorene-9,2'-thiirane] (7f) was prepared along with 2,2-dichloro -3,3-bis(4-methoxyphenyl)thiirane (16), and rospiro[5H-dibenzo[a,d]cyc loheptane-5,2'-thiirane] (17) all of which were stable at room tempera ture. A study of the reactivity of fluorenyl-substituted thiiranes and other related thiiranes showed that the extent of aromaticity of the substituents at the 3-position of the thiiranes influences their stabi lities.