Wenzeng Duan

In this paper, two isostructural cage-type metal–organic frameworks LCU-601(M = Mn2Ti or Al) were synthesized by using the photosensitive carbazole-based carboxylic acid ligand H4PBCD and a presynthesized [Mn2Ti(μ3-O)(CF3COO)6] cluster or in situ generated [Al3(μ3-O)(COO)6] cluster, respectively. Particularly, LCU-601(Al) exhibits excellent structural stability, permanent porosity for N2 and CO2 adsorption, and photoresponsive performance. This material serves as an efficient heterogeneous photocatalyst for the oxidative coupling of thiols into disulfides under mild conditions (room temperature and 1 atm O2) and demonstrates good recyclability and structural integrity during consecutive catalytic cycles. Mechanism studies unveil that photogenerated holes (h+) and superoxide radicals (O2•–) are the crucial active species for the photocatalytic S–S bond formation.

Planar chiral [2.2]paracyclophanyl-based 4H-pyran-4-one and 4-(dicyanomethylene)-4H-pyran derivatives ((R_p)/(S_p)-PCP-2 and (R_p)/(S_p)-PCP-6) were designed and synthesized. Based on their structure- and solvatochromism-dependent tunable photophysical properties, PCP-2 and PCP-6 can serve to construct an acid-induced artificial light-harvesting system with arbitrarily tunable visible emission. By incorporating the planar chirality, acid-induced white circularly polarized luminescence materials were achieved using Förster resonance energy transfer (FRET) strategy. Furthermore, the materials can be used to fabricate white organic light-emitting diodes (WOLEDs).

C ₇₆ H ₆₄ Cu ₄ N ₃ O ₈ , orthorhombic, Cmc 2 ₁ , a = 18.3688(15) Å, b = 12.9739(11) Å, c = 8.1821(8) Å, V = 1949.9(3) Å ³ , Z = 4, R _gt ( F ) = 0.0524, wR _ref ( F ² ) = 0.1283, T = 298(2) K.

A family of microporous titanium-containing metal-organic frameworks (denoted as M₂Ti-CPCDC, M = Mn, Co, Ni) has been synthesized by using a bimetallic [M₂Ti(μ₃-O)(COO)₆] cluster and a tritopic carbazole-based organic ligand H₃CPCDC. M₂Ti-CPCDC are stable and display permanent porosity for N₂ and CO₂ uptake, ranking among the most porous titanium-based metal-organic frameworks. M₂Ti-CPCDC crystals exhibit n-type semiconductor behavior. Further catalytic studies demonstrate that all M₂Ti-CPCDC materials are applicable for triggering photo-oxidative reactions of amines in air. More specifically, amines with electron-donating groups afford the aldehydes as the main products, while amines bearing electron-withdrawing groups give rise to imines as the main product. Among them, Mn₂Ti-CPCDC exhibit the best photocatalytic activity, with conversion of benzylamine up to 99% and selectivity of 99%. Mn₂Ti-CPCDC could be recycled in at least three runs while retaining crystallinity and catalytic activity. The reaction mechanism indicates that photoinduced hole (h⁺), superoxide radical anion (O₂^·-), and singlet oxygen (¹O₂) are the main active species involved in the photo-oxidation process.

Disclosed herein is a rhodium(III)-catalyzed direct heteroarylation reaction between unactivated aliphatic C(sp³)-H bonds in 2-alkylpyridines and heteroaryl organoboron reagents. This catalytic protocol is compatible with various heterocyclic boronates containing ortho- and meta-pyridine, pyrazoles, furan, and quinoline with strong coordination capability. The achievement of this methodology provides an efficient route to build new C(sp³)-heteroaryl bonds.

Pioneering the synthesis of 4-aryl-5-carboxy[2.2]paracyclophanes through C(sp²)–H activation, we constructed distinct small organic molecules possessing circularly polarized luminescence (CPL) with high quantum yields of up to 0.42.

A robust, microporous, and photoactive aluminum-based metal-organic framework (Al-MOF, LCU-600) has been assembled by an in situ-formed [Al₃O(CO₂)₆] trinuclear building unit and a tritopic carbazole ligand. LCU-600 shows a high water stability and permanent porosity for N₂ and CO₂ adsorption. Notably, the incorporation of photoresponsive carbazole moieties into LCU-600 makes it a highly efficient and recyclable photocatalyst for aerobic photo-oxidation of sulfides into sulfoxides under an air atmosphere at room temperature. Mechanism investigations unveil that photogenerated holes (h⁺), superoxide radical anion (O₂^•-), and singlet oxygen (¹O₂) are critical active spices for the photo-oxidation reaction performed in an air atmosphere.