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Herein, we disclose the Ni-catalyzed ring-opening C-O functionalization of peri -xanthenoxanthenes using Grignard reagents that forms 8-monofunctionalized binaphthols. 1,2-Bis(dicyclohexylphosphino)ethane was the best ligand for alkylations and ICy for arylation. After mechanistic investigations, we assumed that the reaction proceeds via C-O reduction and subsequent C-O functionalization. To verify the mechanism, the intermediate after reduction was isolated. Moreover, the asymmetric addition, using 8-octylbinaphthol after optical resolution, was studied.

Continuous tuning of the backbone conformation and interchain distance of a π-conjugated polymer is an essential prerequisite to unveil the inherent electrical and optical features of organic electronics. To this end, applying pressure in a hydrostatic medium or diamond anvil cell is a facile approach without the need for side-chain synthetic engineering. We report the development of high-pressure, time-resolved microwave conductivity (HP-TRMC) and evaluation of transient photoconductivity in the regioregular poly(3-hexylthiophene) (P3HT) film and its bulk heterojunction blend with methanofullerene (PCBM). X-ray diffraction experiments under high pressure were performed to detail the pressure dependence of π-stacking and interlamellar distances in P3HT crystallites and PCBM aggregates. The HP-TRMC results were further correlated with high-pressure Raman spectroscopy and density functional theory calculation. The increased HP-TRMC conductivity of P3HT under pressure was found to be relevant to the planarity of the backbone conformation and intramolecular hole mobility. The effects of pressure on the backbone planarity are estimated to be ∼0.3 kJ mol(-1) based on the compressibility derived from the X-ray diffraction under high pressure, suggesting the high enough energy to cause modulation of the planarity in terms of the Landau-de Gennes free energy of isolated P3HT chains as 0.23 kJ mol(-1). In contrast, the P3HT:PCBM blend showed a simple decrease in photoconductivity irrespective of the identical compressive behavior of P3HT. A mechanistic insight into the interplay of intra- and intermolecular mobilities is a key to tailoring the dynamic π-figuration associated with electrical properties, which may lead to the use of HP-TRMC for exploring divergent π-conjugated materials at the desired molecular arrangement and conformation.

Seven double-armed cyclens bearing two aromatic side-arms, at the 1- and 7-positions of the cyclens, were prepared via three steps from dimethyl 2,2'-iminodiacetate. The X-ray structures of the Ag(+) complexes and Ag(+)-ion-induced (1)H NMR spectral changes suggest that the two aromatic side-arms cover the Ag(+) ions incorporated in the ligand cavities, as if the aromatic ring "petals" catch the Ag(+) ions in the way a real insectivorous plant (Venus flytrap) catches insects, using two leaves. It is also reported that the CH-π interactions between the aromatic side-arms, as well as the Ag(+)-π interactions, are crucial for double- and tetra-armed cyclens to work as argentivorous molecules.

The direct C-H alkynylation of azoles with terminal alkynes proceeds efficiently under a nickel/O(2) catalytic system. On the other hand, a copper/air catalyst enables the coupling of polyfluoroarenes with terminal alkynes. These catalyses provide new accesses to arylacetylenes through the formal direct Sonogashira coupling.

The direct alkynylation reaction of 1,3,4-oxadiazoles with alkynyl bromides efficiently proceeds in the presence of a copper catalyst at room temperature to create the corresponding heteroaryl-alkynyl linkage in good yields. This direct coupling provides a rapid and convergent access to oxadiazole core pi-conjugated systems.

The direct C-H alkynylation of azoles with alkynyl bromides proceeds efficiently in the presence of a nickel-based catalyst system. The reaction enables the introduction of various alkynyl groups bearing aryl, alkenyl, alkyl, and silyl substituents to the azole cores. In some cases, addition of a catalytic amount of CuI is observed to accelerate the direct coupling dramatically.

The cross-addition of terminal silylacetylenes to gamma-arylated propargyl amines occurs efficiently via C-H cleavage by using either a nickel or rhodium catalyst. Taking advantage of the catalyst-controlled switching of regioselectivity in the reaction, both the 2- and 3-alkynylallylamines are readily accessible from the same starting materials.