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The first example of an inorganic-ligand supported iron(III) catalysed coupling of formic acid and amines to form formamides is reported. The pure inorganic catalyst (NH4)3[FeMo6O18(OH)6] (1), which consists of a central FeIII single-atomic core supported within a cycle-shaped inorganic ligand consisting of six MoVIO6 octahedra, shows excellent activity and selectivity, and avoids the use of complicated/commercially unavailable organic ligands. Various primary amines and secondary amines have been successfully transformed into the corresponding formamides under mild conditions, and the formylation of primary diamines has also been achieved for the first time. The Fe catalyst 1 can be reused several times without appreciable loss of activity. [ABSTRACT FROM AUTHOR]

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[NiMo6O18(OH)6] (1), which consists of pure inorganic framework built from a central NiII core supported by six MoVIO6 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. 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[NiMo6O18(OH)6] using molecular oxygen and visible light. This method utilizes mainly an inorganic polymolybdate ligand to support the Ni2+ 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. [ABSTRACT FROM AUTHOR]

Herein, we divulge an efficient protocol for aerobic oxidation of alcohols with an inorganic-ligand supported iodine catalyst, (NH4)5[IMo6O24]. The catalyst system is compatible with a wide range of groups and exhibits high selectivity, and shows excellent stability and reusability, thus serving as a potentially greener alternative to the classical transformations. [ABSTRACT FROM AUTHOR]

Abstract: A method for the aerobic oxidation of aldehydes to carboxylic acids in water by using an inorganic‐ligand‐supported copper catalyst was developed. This method was performed with the use of atmospheric oxygen as the sole oxidant under extremely mild aqueous conditions, and furthermore, a wide range of aldehydes with various functional groups were tolerated. The copper catalyst could be recycled and used in successive reactions at least six times without any appreciable degradation in performance. This method is operationally simple and avoids the use of high‐costing, toxic, air/moisture‐sensitive, and commercially unavailable organic ligands. The generality of this method gives it potential to be used on the industrial scale. [ABSTRACT FROM AUTHOR]

Most state-of-art transition-metal catalysts usually require organic ligands, which are essential for controlling the reactivity and selectivity of reactions catalyzed by transition metals. However, organic ligands often suffer from severe problems including cost, toxicity, air/moisture sensitivity, and being commercially unavailable. Herein, we show a simple, mild, and efficient aerobic oxidation procedure of amines using inorganic ligand-supported non-precious metal catalysts 1, (NH4) n[MMo6O18(OH)6] (M=Cu2+; Fe3+; Co3+; Ni2+; Zn2+, n=3 or 4), synthesized by a simple one-step method in water at 100 °C, demonstrating that the catalytic activity and selectivity can be significantly improved by changing the central metal atom. In the presence of these catalysts, the catalytic oxidation of primary and secondary amines, as well as the coupling of alcohols and amines, can smoothly proceed to afford various imines with O2 (1 atm) as the sole oxidant. In particular, the catalysts 1 have transition-metal ion core, and the planar arrangement of the six MoVI centers at their highest oxidation states around the central heterometal can greatly enhance the Lewis acidity of catalytically active sites, and also enable the electrons in the center to delocalize onto the six edge-sharing MO6 units, in the same way as ligands in traditional organometallic complexes. The versatility of this methodology maybe opens a path to catalytic oxidation through inorganic ligand-coordinated metal catalysis. [ABSTRACT FROM AUTHOR]

The first example of a heterogeneous iron(III)-catalyzed aerobic oxidation of aldehydes in water was developed. This method utilizes 1 atmosphere of oxygen as the sole oxidant, proceeds under extremely mild aqueous conditions, and covers a wide range of various functionalized aldehydes. Chromatography is generally not necessary for product purification. Its operational simplicity, gram-scale oxidation, and the ability to successively reuse the catalyst, make this new methodology environmentally benign and cost effective. The generality of this methodology gives it the potential to be used on an industrial scale. [ABSTRACT FROM AUTHOR]

The first example of a heterogeneous iron(III)-catalyzed aerobic oxidation of aldehydes in water was developed. This method utilizes 1 atmosphere of oxygen as the sole oxidant, proceeds under extremely mild aqueous conditions, and covers a wide range of various functionalized aldehydes. Chromatography is generally not necessary for product purification. Its operational simplicity, gram-scale oxidation, and the ability to successively reuse the catalyst, make this new methodology environmentally benign and cost effective. The generality of this methodology gives it the potential to be used on an industrial scale. [ABSTRACT FROM AUTHOR]

A practical, efficient and environmentally benign catalytic protocol for the oxidative cross-coupling reaction of halides with amines, oxidative self-coupling of amines and oxidation of halides was developed with inorganic-ligand supported ZnPOM (NH4)4[ZnMo6O18(OH)6] using molecular oxygen. This method mainly utilizes an inorganic polymolybdate ligand to support the Zn2+ ion, avoiding the use of complicated organic ligands.