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N-Heterocyclic carbene (NHC), generated in situ from easily available N-heterocyclic imidazolium salt with air as terminal oxidant, has successfully been utilized as a cheap and efficient catalyst for onepot aerobic oxidative synthesis of 2-arylbenzo[d]oxazoles, 2-substituted benzo[d]thiazoles, and 1,2-disubstituted benzo[d]imidazoles. [ABSTRACT FROM AUTHOR]

Several N-heterocyclic carbene palladium catalyzed oxidation of nonactivated sp3C–H bonds in linear primary and secondary trifluoroacetic acid esters have been developed. A high selectivity for the oxidation of the omega-1 carbon atom in trifluoroacetic acid n-propyl to n-octyl esters was realized by an appropriate choice of N-heterocyclic carbene palladium complexes. [ABSTRACT FROM AUTHOR]

Metalladichalcogenolate cluster complexes [Cp′Co{E2C2(B10H10)}]{Co2(CO)5} [Cp′ = η5-C5H5, E = S(3a), E = Se(3b); Cp′ = η5-C5(CH3)5, E = S(4a), E = Se(4b)], {CpCo[E2C2(B10H10)]}2Mo(CO)2] [E = S(5a), Se(5b)], Cp*Co(µ2-CO)Mo(CO)(py)2[E2C2(B10H10)] [E = S(6a), Se(6b)], Cp*Co[E2C2(B10H10)]Mo(CO)2[E2C2(B10H10)] [E = S(7a), Se(7b)], (Cp′Co[E2C2(B10H10)]W(CO)2 [E2C2(B10H10)] [Cp′ = η5-C5H5, E = S(8a), E = Se(8b); Cp′ = η5-C5(CH3)5, E = S(9a), E = Se(9b)], {CpCo[E2C2(B10H10)]}2Ni [E = S(10a), Se(10b)] and 3,4-(PhCN4S)-3,1,2-[PhCN4SCo(Cp)S2]-3,1,2-CoC2B9H812 were synthesized by the reaction of [Cp′CoE2C2(B10H10)] [Cp′ = η5-C5H5, E = S(1a), E = Se(1b); Cp′ = η5-C5(CH3)5, E = S(2a), E = Se(2b)] with Co2(CO)8, M(CO)3(py)3 (M = Mo, W), Ni(COD)2, [Rh(COD)Cl]2, and LiSCN4Ph respectively. Their spectrum analyses and crystal structures were investigated. In this series of multinuclear complexes, 3a,b and 4a,b contain a closed Co3 triangular geometry, while in complexes 5a–7b three different structures were obtained, the tungsten–cobalt mixed-metal complexes have only the binuclear structure, and the nickel–cobalt complexes were obtained in the trinuclear form. A novel structure was found in metallacarborane complex 12, with a B–S bond formed at the B(7) site. The molecular structures of 4a, 5a, 6a, 7b, 9a, 9b, 10a and 12 have been determined by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Characterizes bis(dicyanamido)(diethylenetriamine-κ[sup 3]N)copper(II) and (dicyanamido)-(triethylenetetramien-κ[sup 4]N)copper(II)dicyanamide using single-crystal x-ray diffraction. Role of the hydrogen-bond interactions between the uncoordinated terminal nitrogen atoms of two dicyanamide ions and the amine hydrogen atoms in forming three-dimensional networks; Distortion of the tetragonal pyramid. .

New 4-acetylbenzyl-N-heterocyclic carbene ligands (1-4) have been used to synthesize iridium complexes 6-9 and ruthenium complex 10. All complexes were characterized by FT-IR, ¹H and 13C NMR spectroscopy, elemental analysis, and in the case of 6, by X-ray diffraction studies. The catalytic performance of these iridium and ruthenium complexes for transfer hydrogenation of ketones and imines and N-alkylation of amines with primary alcohols were tested in a range of substrates, and showed high catalytic activity with 1 mol% catalytic loading. The neutral complex 8 with two acetyl groups also showed good catalytic efficiency under lower catalyst loading (0.01 mol%), with the maximum TON of 8000, while on the other hand, the cationic complex 9 with PF6- as counteranion showed good to excellent catalytic activity toward the N-alkylation of amines in a wide scope of substrates. We also found out that the Ir complex 6' was formed through the intramolecular CH activition of 6 under the transfer hydrogenation conditions. [ABSTRACT FROM AUTHOR]