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Water-soluble 2N2O–Cu(II) complexes were synthesized and used for the catalytic oxidation of benzylic alcohols to the corresponding aldehydes in pure water resulting in high yields of up to 94%. Importantly, the catalytic system exhibits a wide substrate scope, high functional group tolerance and can be reused directly for subsequent reaction cycles. Using this catalytic system, the product 4-methylbenzaldehyde can be produced on a multi-gram scale and in the complete absence of any organic solvent, surfactant or phase transfer reagent. Copyright © 2016 John Wiley & Sons, Ltd.

A simple and efficient catalytic system for Na2PdCl4 catalyzing the Suzuki-Miyaura reaction of dibromobenzene and arylboronic acid has been developed by using 2N2O-salen as a ligand in H2O/EtOH (V:V=4:1) at 100°C. Using this method, the reactions of substrates containing sterically demanding ortho substituents (e.g. dibromobenzene and/or arylboronic acids) proceeded efficiently, with the corresponding terphenyl derivatives being produced in moderate to excellent yields. Furthermore, this method offers interesting features for the multi-gram scale synthesis of terphenyl compound.

Water-soluble 2N 2 O-salen ligands and their palladium complexes were synthesized and used as efficient catalysts for the Suzuki–Miyaura reactions in pure water. Notably, the reactions of substrates with sterically demanding ortho substituents (aryl bromides and/or arylboronic acids) proceed smoothly to generate corresponding products with moderate to high yields using 0.5 mol % (salph)Pd (salph N , N ′-bis(4-SO 3 Na-salicylidene)-1,2-phenylenediamine) as the catalyst. Importantly, the catalytic system has the wide substrate scope and the high tolerance to various functional groups, including cyano, amino, nitro, methoxy, and acetyl. Moreover, the biaryl compounds were also obtained on a multi-gram scale by simple recrystallization with the system in the absence of any organic solvent, surfactant, or phase transfer agent and the catalyst was reused directly for the next cycle. Particularly, this protocol can be applied to synthesize aryl-substituted carbazolyl compounds.

Ba1.9Ca2.4Mg9.7Si7 was grown as large crystals from the reaction of silicon with barium and calcium in Mg/Al flux. This compound is a charge-balanced Zintl phase with the Zr2Fe12P7 structure type in hexagonal space group P6 (a = 11.196(2) A, c = 4.4595(9) A); barium occupies the Zr sites, the lighter alkaline earths (Mg, Ca) mix on the Fe sites, and silicon occupies the phosphorus sites. An isostructural germanide (Ba1.2Sr0.9Mg11.9Ge7, a = 11.064(1) A, c = 4.3709(6) A)) was similarly synthesized from reactions of germanium with barium and strontium in Mg/Al flux. Density of states calculations indicate these phases are semimetals, in agreement with their charge-balanced nature. Measurements of electrical resistivity, thermal conductivity, and Seebeck coefficient were carried out from 300–1000 K to investigate the thermoelectric properties of Ba1.9Ca2.4Mg9.7Si7. This compound is an n-type semimetal with low thermal conductivity (2 W/(m·K)), moderate Seebeck coefficient (−200 μV/K at 900 K), and a thermoel...

A general, yet efficient synthesis method of 9-arylfluorenes via metal-free reductive coupling of N-tosylhydrazones and arylboronic acids has been developed. This methodology is realized by a one-pot protocol in two steps involving the preparation of N-tosylhydrazones by reacting tosylhydrazide with 9-fluorenone derivatives, followed by the reductive coupling of arylboronic acid in the presence of potassium carbonate to afford various 9-arylfluorenes analogues in moderate to excellent yields. Importantly, the catalytic system presented here enables the use of easily accessible starting materials and can be employed on a wide variety of substrates with good functional group tolerance. This protocol could also be particularly useful for the synthesis of 9-fluorenyl-substituted carbazolyl compounds.

Single crystals of Mg-substituted CeFe2Al8-type intermetallics LnFe2MgxAl8-x (Ln: La—Nd, Sm; x ≤ 1) are grown by reaction of Fe and Ln in a 1:1 Mg/Al reactive flux (steel capsules in evacuated silica tubes, 950 °C, 5 h; controlled cooling).

An efficient and inexpensive direct alkynylation of trifluoromethyl ketones (I) is developed without using any additional ligands.

3-(Diphenylphosphino)propanoic acid ( L2 ) has proved to be an efficient ligand for the copper-catalyzed C N coupling reactions. N -arylation of imidazoles with aryl iodides catalyzed by CuCl/ L2 was smoothly carried out in DMSO at 100 °C with a yield up to 98%. N -arylation of 1 H -pyrazole with aryl iodides and bromides catalyzed by Cu(OAc) 2 / L2 in 1,4-dioxane also gave the corresponding products with yields of 40%–98%.

The use of Pd(OAc)2/PCy3 as catalyst system in the presence of potassium phosphate gives a rapid and simple access to the title derivatives including the synthesis of 4-vinylbiphenyl liquid crystal compounds such as (Vf).

Tetrazole-1-acetic acid was found to serve as a superior ligand for CuI-catalyzed N-arylation of imidazoles with aryl iodides under a low catalyst loading (5 mol% of CuI). A variety of aryl iodides could be aminated to provide the N-arylated products in good to excellent yields without the need of an inert atmosphere.

Metallomicelles of palladium(II) complex 4 are found to be an efficient catalyst for Suzuki–Miyaura reactions of aryl bromides substituted with a long alkyl chain and arylboronic acids at 80 °C in neat water. The reactions proceed smoothly to generate the corresponding biaryl compounds in moderate to excellent yields. Various biphenyl derivatives were successfully obtained by complex 4 catalysis of the Suzuki–Miyaura reactions in the absence of any surfactants in neat water. Copyright © 2013 John Wiley & Sons, Ltd.

Four inexpensive and air-/moisture-stable pyrrolecarbaldiminato-Cu complexes 1–4 were synthesized and evaluated to be a novel class of catalysts for the N-arylation of imidazoles with aryl halides. A variety of aryl iodides, bromides and activated aryl chlorides underwent the coupling with imidazoles, promoted by the catalyst 4, in moderate to good yields without the protection by an inert gas.

Yb2.77FeAl3.72Mg0.28Si2, Dy3-δFeAl4-xMgxSi2, Y3-δFeAl4-xMgxGe2, Er3-δFeAl4-xMgxGe2, and Yb5Fe4Al17Si6 are synthesized from the elements using an equimolar Mg/Al reactive flux (950 °C, 5 h).

Highest yields of crystalline EuMgSn are prepared by melting of Mg, Al, Sn, and Eu in a molar ratio of 15:15:2:1 (Nb crucible in sealed silica tubes, 1.

The compounds Ln5Mg5Fe4Al12Si6 (Ln: Gd, Dy, Y) are synthesized by reaction of Fe, Si, and Ln in an equimolar Mg/Al flux (750 °C, 24 h).