Dichalcogen-Bridged Acenaphthenes as New Electron Donors

Abstract

Three new electron donors, 5,6-dihydroacenaphtho[5,6-cd]-1,2-dithiole (1a), -diselenole (1b), and -ditellurole (1c) have been prepared with a view to developing new electron donors for low-dimensional molecular complexes. Their donor characters are markedly enhanced as compared with the corresponding dichalcogen-bridged naphthalenes. They formed charge-transfer complexes with tetracyanoquinodimethane (TCNQ). Their electrical conductivities increase in the order of polarizable chalcogen. The crystal structures of 1a–TCNQ complex and neutral 1c were determined by X-ray analyses. In the crystal, 1a and TCNQ form a unique mixed stack, that is, a pair of donors and a pair of acceptors make an alternately stacking column. Neutral 1c takes an almost planar conformation and molecules are connected to each other with strong Te–Te interactions.

Analysis of One‐Bond Se‐Se Nuclear Couplings in Diselenides and 1,2‐Diselenoles on the Basis of Molecular Orbital Theory: Torsional Angular Dependence, Electron Density Influence, and Origin in 1J(Se, Se)

“…They are usually small ( 1 J obsd (Se, Se: 1 ) ≤ 64 Hz; see Table 1). We examined 1 J (Se, Se) of naphto[1,8- c,d ]-1,2-diselenole (4-Y-1,8-Se 2 C 10 H 5 ( 2 ): Y = H ( a ) [11–15], OMe ( b ), Me ( c ), Cl ( d ), COOMe ( e ), CN ( f ), and NO 2 ( g )), which correspond to the symperiplanar diselenides (Figure 1). The 1 J (Se, Se) values are measured for 2c , 2d , and 2g , and large 1 J obsd (Se, Se) values of 330–380 Hz are detected.…”

Platinum Complexes of 5,6‐Dihydroacenaphtho[5,6‐cd]‐1,2‐dichalcogenoles

“…The homogeneity of the new compounds was, where possible, confirmed by microanalysis. 5,cd]-1,2-dithiole (AcenapS 2 ) L1 and 5,6-dihydroacenaphtho [5,6-cd]-1,2-diselenole (AcenapSe 2 ) L2 were prepared following standard literature procedures [23] starting from 5,6-dibromoacenaphthene. [24] Synthesis of the platinum metal complexes was based on previously well documented routes to complexes of 1,8-disubstituted naphthalene chalcogenides and related polyaromatic hydrocarbon compounds.…”

“…[23] To a stirred solution of 5,6-dibromoacenaphthene (5.0 g, 16.03 mmol) and TMEDA (4.8 mL, 16.03 mmol) in diethyl ether (200 mL) was slowly added a 2.5 M hexane solution of n-butyllithium (6.4 mL, 16.03 mmol) at -78°C. After the mixture was stirred for 15 min at this temperature, sulfur flowers (0.51 g, 16.03 mmol) were added and stirring was continued at -40 °C for 2 h. The mixture was cooled again to -78°C, after which a 2.5 M hexane solution of n-butyllithium (6.4 mL, 16.03 mmol) was added and the reaction mixture stirred at this temperature for 15 min.…”

RCNSSS+: A novel class of stable sulfur rich radical cations

“…3.3-3.5Å. System 20 forms charge-transfer complex with TCNQ [104]. In the solid state mixed stacks of 20 ␦+ · · ·TCNQ ␦− are observed, in which the degree of charge separation is expected to be less than one.…”