Visible‐Light‐Driven Photocatalytic Oxidation of Organic Chlorides Using Air and an Inorganic‐Ligand Supported Nickel‐Catalyst Without Photosensitizers. Issue 19 (9th August 2018)

• Record Type: Journal Article
• Authors: Yu, Han; Wang, Jingjing; Zhai, Yongyan; Zhang, Mengqi; Ru, Shi; Han, Sheng; Wei, Yongge
• Is Part Of: ChemCatChem. Volume 10:Issue 19(2018)
• Page Start: 4274
• Page End: 4279
• Publication Date: 2018-08-09
• Subjects: Polyoxometalates -- chlorides -- imine derivative -- photocatalytic -- nickel catalysts; Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.201800629
• Languages: English
• ISSNs: 1867-3880

Abstract

Abstract: Engineering photoredox‐triggered chemical transformation via visible light has been an emerging area in organic synthesis. However, most of the well‐established photocatalysts are based upon either transition metal complexes involved with noble metals and organic ligands or photosensitive organic dyes, the development of pure inorganic molecular photocatalysts that could provide better stability and durability is greatly retarded. Herein we discover that the Anderson polyoxometalate (POM) Na4 [NiMo6 O18 (OH)6 ] (1 ), which consists of pure inorganic framework built from a central Ni II core supported by six Mo VI O6 inorganic scaffold/ligands, can be used as a powerful photocatalyst. Upon irradiation with visible light (>400 nm), the compound can catalyze, in high efficiency, a wide range of reactions, including the oxidative cross‐coupling reaction of chlorides with amines, as well as oxidation of chlorides using molecular oxygen, affording various imines, aldehydes, and ketones, respectively in high selectivity and good yields. Owing to the robust inorganic framework, this catalyst exhibits excellent stability during the catalysis and reusability with little loss of the catalytic activity, thus providing an alternative without use of complicated organic ligands and expensive noble metal‐based photosensitizers. Abstract : Best supporting role : A practical and efficient environmentally benign catalytic protocol of oxidation of cross‐coupling reaction of chlorides with amines, as well as oxidation of halides was developed with inorganic‐ligand supported Ni‐photocatalyst Na4 [NiMo6 O18 (OH)6 ] using molecular oxygen and visible light. This method utilizes mainly an inorganic polymolybdate ligand to support the Ni 2+ ion and 1 atm O2 gas as the sole oxidant, which can smoothly proceed to afford various imines and aldehydes or ketones with high yields and selectivity, avoiding the use of complicated organic ligands and expensive noble metal‐based photosensitizers.