Synthesis of Substituted Picenes through Pd-Catalyzed Cross-Coupling Reaction/Annulation Sequences and Their Physicochemical Properties

Abstract

A novel and versatile synthetic method for picene derivatives is developed using the Pd-catalyzed intramolecular double cyclization of the corresponding 2,3-bis[(1Z)-2-phenylethenyl]-1,4-dichlorobenzenes, which are readily prepared by Suzuki-Miyaura cross-coupling reactions of polyhalobenzenes with (Z)-arylethenylboronates. The physical properties of the obtained picenes can be modified via introducing a variety of functional groups to the picene framework. All compounds are investigated by UV-vis and fluorescence spectroscopic measurements, CV, and DFT calculations as well as X-ray diffraction analysis.

Synthesis of Substituted [6]Phenacenes through Suzuki–Miyaura Coupling of Polyhalobenzene with Alkenylboronates and Sequential Intramolecular Cyclization via C–H Bond Activation

“…Herein, we report the synthesis, characterization, and physicochemical properties of unsymmetrically substituted [6]phenacenes, for the first time, using our synthetic strategy for the synthesis of [5]phenacenes, which was recently established. 7 The first set of experiments examined the reaction conditions of the SuzukiMiyaura coupling of 1,4-dichloro-2,3-diiodobenzene (1) with a slight excess of (Z)-2-(1-naphthyl)-ethenylboronate 2, prepared by Rh-catalyzed stereoselective hydroboration of terminal alkynes. 8 The results are summarized in Table 1.…”

“…7 However, the desired product 3 was obtained in only 22% yield, because of concurrent protodeborylation of 2 ( With the synthesized 3 in hand, we conducted a second cross-coupling with the synthesized alkenylboronates 4a4d as the coupling partners. The PEPPSI-IPr catalyst gave rise to the corresponding [6]phenacene precursors 5a5d in 6383% yields (Table 2).…”

Transistor Properties of 2,7-Dialkyl-Substituted Phenanthro[2,1-b:7,8-b′]dithiophene

“…Field-effect transistors (FETs) using thin films and single crystals of phenacene-type molecules (extended W-patterned structures of fused benzene rings) have been extensively studied using various gate dielectrics123456789101112131415161718. The highest field-effect mobility ( μ ) reported in these phenacene thin-film FETs is currently 21 cm 2  V −1 s −1 .…”

Synthesis of Dinaphtho[2,3-d:2’,3’-d’]anthra[1,2-b:5,6-b’]dithiophene (DNADT) Derivatives: Effect of Alkyl Chains on Transistor Properties

“…During our continuing studies on synthesis and characterization of an array of π-conjugated phenacene-type molecules for OFET properties [21][22][23][24][25][26][27][28][29][30][31], we have reported an efficient synthetic route and transistor properties of nine-ring-fused thienoacene molecule (dinaphtho [2,3-d:2',3'-d'] anthra [1,2-b:5,6-b']dithiophene (DNADT), Figure 1a) [32]. In addition, the fabricated OFET devices based on DNADT exhibited the hole mobility of up to 8.5 × 10 −2 cm 2 V −1 s −1 .…”