Ryotaro Tsuji

Stabilization of the 1-naphthyltropylium ion by [2.2]paracyclophane fixed at the face-to-face position to the tropylium ring

Abstract The title cation, in which [2.2]paracyclophane and the tropylium ring are rigidly fixed at the face-to-face arrangement, was synthesized, and was found to exhibit the highest stability in a series of (8-substituted 1-naphthyl)tropylium ions prepared so far.

Stereomutation of endo-2-phenyl-endo-6-tropyliobicyclo[2.2.2]octane to the exo-6-tropylio isomer. Steric repulsion between the phenyl and tropylium rings showing intramolecular charge-transfer

Abstract endo-2-Phenyl-endo-6-tropyliobicyclo[2.2.2]octane 2 exhibits intramolecular charge-transfer (CT) interaction, but rearranges to exo-6-tropylio isomer 3 in acetonitrile with the 2/3 ratio of ca.0.07 at equilibrium. This ratio indicates that the steric repulsion between the face-to-face phenyl and tropylium rings at ca.2.5A is estimated to be at least ca.1.6kcal/mol.

4-Homoadamantyne: generation, chemical trapping and structure of its Pt(0) complex

A highly strained polycyclic alkyne with a cage structure, 4-homoadamantyne 2, has been generated and trapped with diphenylisobenzofuran and by complexation with Pt(0); X-ray crystallography of the Pt(0) complex 4 and molecular mechanics calculations for 2 indicate that the molecular strain in 2 and in 4 is nearly as large as that in cyclohexyne and in its Pt(0) complex.