Copper‐Based Ternary and Quaternary Semiconductor Nanoplates: Templated Synthesis,Characterization, and Photoelectrochemical Properties

Two‐dimensional (2D) copper‐based ternary and quaternary semiconductors are promising building blocks for the construction of efficient solution‐processed photovoltaic devices at low cost. However, the facile synthesis of such 2D nanoplates with well‐defined shape and uniform size remains a challenge. Reported herein is a universal template‐mediated method for preparing copper‐based ternary and quaternary chalcogenide nanoplates, that is, CuInS₂, CuIn_xGa_1?xS₂, and Cu₂ZnSnS₄, by using a pre‐synthesized CuS nanoplate as the starting template. The various synthesized nanoplates are monophasic with uniform thickness and lateral size. As a proof of concept, the Cu₂ZnSnS₄ nanoplates were immobilized on a Mo/glass substrate and used as semiconductor photoelectrode, thus showing stable photoelectrochemical response. The method is general and provides future opportunities for fabrication of cost‐effective photovoltaic devices based on 2D semiconductors.     

Copper‐Catalyzed Synthesis of γ‐Amino Acids Featuring Quaternary Stereocenters

The first general asymmetric synthesis of γ,γ‐disubstituted γ‐amino acids by copper‐catalyzed ring opening of nonstrained lactones with amines is reported. This approach features ample scope, operational simplicity, and wide functional‐group diversity. The catalytic process allows access to a series of highly functionalized enantioenriched γ‐amino acids featuring quaternary stereocenters with excellent enantiomeric ratios of up to 98:2 and excellent yields of up to 98 %.     

Photoinduced Copper‐Catalyzed Regioselective Synthesis of Indoles: Three‐Component Coupling of Arylamines,Terminal Alkynes,and Quinones

The first successful example of a visible‐light‐induced copper‐catalyzed process for C H annulation of arylamines with terminal alkynes and benzoquinone is described. This three‐component reaction allows use of a variety of commercial terminal alkynes as coupling partners for the one‐step regioselective synthesis of functionalized indoles. Moreover, the current process represents a sustainable and atom‐economical approach for the preparation of complex indoles from easily accessible starting materials under visible‐light irradiation, without the need for expensive metals and harsh reaction conditions.