Charge-Transfer Complexes of PXX (PXX = 6, 12-Dioxaanthanthrene). The Formal Charge and Molecular Geometry

Abstract

Three kinds of charge-transfer (CT) complexes of PXX (PXX = 6, 12-dioxaanthanthrene) have been newly prepared and structurally characterized. In the 1 : 2 CT complex with TNP (TNP = 2,4,6-trinitrophenol), PXX is practically neutral. In the semiconducting partially oxidized salt with I3, the PXX molecules form a trimer and each PXX is formally oxidized by e/3. In the 3 : 2 salt with [Ni(mnt)2]- (mnt = maleonitriledithiolate), the PXX molecules again form a trimer unit and each PXX is formally oxidized by 2e/3. Together with the structural data obtained from the PXX single component crystal, the molecular geometry change by the formal charge on PXX has been examined. A noticeable change has been found in the aromatic ring framework, which is consistent with the distribution of the HOMO coefficients obtained from the extended Hückel calculation.

Structural Dynamics and Barrier Crossing Observed for a Fluorescent O‐Doped Polycyclic Aromatic Hydrocarbon

“…The compound, PXX, was obtained as a yellow crystalline solid, with both 1 H and 13 C NMR spectra being fully consistent with the proposed molecular formula. The X‐ray crystal structure determined at 150 K (see the Supporting Information) was found to be in good agreement with that reported previously at room temperature.…”

“…Assuming the twisting movement is equivalenttotranslational motion about the ether linkages, Kramers' theory allows estimation of the potential curvature at the apex of the barrier. compound, PXX, was obtained as ay ellow crystalline solid, with both 1 Ha nd 13 CNMR spectra being fully consistent with the proposed molecular formula.T he X-ray crystal structure determined at 150 K( see the Supporting Information) was found to be in good agreement with that reported [19] previously at room temperature.…”

“…300 °C) or undesirable solvents such as benzene have been employed. We opted to slightly adapt a published method since in our hands the purification of the crude material was straightforward, and the yield was reasonable for a medium‐scale synthesis (Scheme ). The compound, PXX, was obtained as a yellow crystalline solid, with both 1 H and 13 C NMR spectra being fully consistent with the proposed molecular formula.…”

“…300 8C) or undesirable solvents such as benzene have been employed. We opted to slightly adapt ap ublished method [19] since in our hands the purification of the crude materialw as straightforward, and the yield was reasonable for am edium-scale synthesis (Scheme 1). The…”

Supramolecular isomerism in the hydrogen-bonded network of (5R,10R)-3,8-dihydroxy-5,10-diethoxy-5,10-dihydrochromeno[5,4,3-cde]chromene monohydrate

“…The reaction process might involve firstly the dimerization of the initial 3,4-dihydroxybenzaldehyde via coupling of the a-C atoms, which is known as radical coupling reaction for phenols during its oxidation with dioxygen catalyzed by some metal compounds [11]. Then the closure of two pyrone rings and the formation of the final product were formed by condensation between each pair of the hydroxyl group and the vicimal carbonyl of another benzene system, and followed by the attacking of ethanol (Scheme 1) which is similar to the reported formation of pseudoskyrin diethyl ether from skyrin [12] and the formation of 6,12-dioxaanthantrene from 1,1¢-bi-2-naphthol [13]. The molecular structure of 1 is shown in Fig.…”