Copper-Bridged Tetrakis(4-ethynylphenyl)ethene Aggregates with Photo-Regulated 1 O 2 and O 2 .- Generation for Selective Photocatalytic Aerobic Oxidation.

Active species regulation is a key scientific issue that essentially determines the selectivity and activity of a photocatalyst. Herein, Cu I -bridged tetrakis(4-ethynylphenyl)ethene aggregates (T 4 EPE-Cu) with photo-regulated 1 O 2 and O 2 .- generation were demonstrated for selective photocatalytic aerobic oxidation. In this system, transient photovoltage combined with the density functional theory calculations confirmed that Cu-alkynyl was the main oxygen activation site. The adsorbed O 2 tends to produce O 2 .- because of the potential well effect of Cu-alkynyl under high-energy light excitation. But under low-energy light, O 2 tends to produce 1 O 2 via resonance energy transfer with Cu-alkynyl. For α-terpinene oxidation, the ratios of 1 O 2 products to O 2 .- products can be controlled from 1.3 (380 nm) to 10.7 (600 nm). Furthermore, T 4 EPE-Cu exhibited ultrahigh photocatalytic performance for Glaser coupling and benzylamine oxidation, with a conversion and selectivity of over 99 %.