Synthesis of substituted fluorenones and substituted 3',3'-dichlorospiro[fluorene-9,2'-thiiranes] and their reactivities
摘要:
Several novel 9-fluorenones were synthesized and were used as precursors in an attempt to prepare unique substituted 3',3'-dichlorospiro[fluorene-9,2'-thiiranes]. Several of the thiiranes were unstable and desulfurized during their preparation (7a-d,11,12). 3',3'-Dichloro(2,5-dimethoxyspiro[fluorene-9,2'-thiirane] (7f) was prepared along with 2,2-dichloro-3,3-bis(4-methoxyphenyl)thiirane (16), and 3',3'-dichloro-10,11-dihydrospiro[5H-dibenzo[a,d]cycloheptane-5,2'-thiirane] (17) all of which were stable at room temperature. 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 stabilities.
We have observed the inversion of the solvation environment of a one‐dimensional solid by low‐temperature scanning tunneling microscopy. Adsorption of 3‐methoxy‐9‐diazofluorene on Ag(111) yields highly oriented supramolecular chains, which are then exposed to water molecules. The annealing of dry and water‐decorated chains results in diametrically opposed outcomes. While the former simply leads to