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A series of 2-arylamino-1,3-selenazoles was synthesized and their reactivity was studied. The 2-arylamino-1,3-selenazoles and their reaction products were characterized by various spectroscopic methods and X-ray diffraction. In addition, the antimicrobial activity of the 2-arylamino-1,3-selenazoles in a panel of seven bacteria and fungi was examined.

This Minireview discusses catalytic asymmetric conjugate addition and allylic alkylation reactions where the nucleophiles were generated in situ by hydrometallation or carbometallation. This exciting recent trend in asymmetric catalysis promises to expand the range of transformations available for the rapid and selective assembly of complex, functional molecules for both academic and industrial research. This Minireview aims to serve as a reference for studies reported to date and discusses the current state-of-the-art, scope and limitations of these processes. [ABSTRACT FROM AUTHOR]

Abstract: Treatment of N,N-dialkyl-4-[4-nitrophenyl)diazenyl] anilines with a mercury(II) salt in anhydrous trifluoroacetic acid results in single and double metallation of the ring with less electron density. The seemingly counterintuitive outcome of the reaction was rationalized through experimental and computational investigations of the reaction mechanism. [Copyright &y& Elsevier]

Abstract: The reaction of di(2-pyridylmethyl)amine with FeCl2 yields [Fe{HN(CH2Py)2}2]Cl2 (1) with the tridentate amines coordinating in a facial manner at the iron(II) center. Transamination of this amine with [M{N(SiMe3)2}2] in an equimolar ratio leads to the formation of heteroleptic [(Me3Si)2N-M{μ-N(CH2Py)2}]2 [M = Mn (2a), Fe (2b), and Zn (2c)]. The metallation of di(2-pyridylmethyl)amine with dimesityl iron(II) gives [Mes-Fe{μ-N(CH2Py)2}]2 (3). At temperatures below −30 °C the transamination reaction of [Fe{N(SiMe3)2}2] with di(2-pyridylmethyl)amine in a molar ratio of 1:2 yields [Fe{N(CH2Py)2}2] (4). The reaction of [Co{N(SiMe3)2}2] with HN(CH2Py)2 leads to the formation of [Co{N(CHPy)2}2] (5b) with 1,3-di(2-pyridyl)-2-azaallyl ligands, regardless of the employed stoichiometry. The compounds 2b, 2c, 3, and 4 have to be handled and manipulated at low temperatures because they degrade already at room temperature whereas the manganese(II) derivative 2a is stable under these conditions. The degradation products [M{N(CHPy)2}2] [M = Fe (5a), Zn (5c)] contain the 1,3-di(2-pyridyl)-2-azaallyl ligands and can be considered as the dehydrogenation products of [M{N(CH2Py)2}2]. A metathetical approach via the reaction of lithium di(2-pyridylmethyl)amide with FeCl2 did not give the desired product 4 but a mixture of 1 and 5a. A 1H NMR and EPR spectroscopic pursuit of the degradation of [(Me3Si)2N-Zn{μ-N(CH2Py)2}]2 (2c) in tetrahydrofuran at temperatures between 253 and 328 K showed diminishing amounts of 2c and the appearance of 1,3-di(2-pyridyl)-2-azaallyl anions whereas the EPR experiments clearly verify the presence of di(2-pyridylmethyl)aminyl radicals in solution. [Copyright &y& Elsevier]

THF proved to be the favoured solvent for the direct synthesis of phenylcalcium iodide. However, ether degradation is the major side reaction in this solvent. Zinc-mediated degradation of THF leads to the formation of the cage compound [{(thf)Ca(O–CH＝CH2)2}4 · CaO · CaI2] (1) besides the zincate [(thf)6Ca] [ZnEt2Ph2]. The structure of 1 shows an oxygen-centered Ca6 octahedron with iodine atoms bound to two opposite corners. Heating of phenylcalcium iodide in THF solution for several hours yields [(CaO)4 · 4 (thf)3CaI2] (2) with a central Ca4O4 heterocubane unit. NMR monitoring of the reaction shows that the phenyl groups are converted to benzene due to α-deprotonation of THF. [Copyright &y& Elsevier]

A series of 2-arylamino-1,3-selenazoles was synthesized and their reactivity was studied. The 2-arylamino-1,3-selenazoles and their reaction products were characterized by various spectroscopic methods and X-ray diffraction. In addition, the antimicrobial activity of the 2-arylamino-1,3-selenazoles in a panel of seven bacteria and fungi was examined. [ABSTRACT FROM AUTHOR]

Abstract: Transamination of Zn[N(SiMe3)2]2 with 8-(triisopropylsilylamino) (1a) and 8-(tert-butyldimethylsilylamino)quinoline (1b) yields monomeric heteroleptic bis(trimethylsilyl)amido zinc 8-(trialkylsilylamido)quinoline (2a, 2b). The reaction of Zn[N(SiMe3)2]2 with 8-aminoquinoline leads to the formation of heteroleptic dimeric 8-amidoquinoline zinc bis(trimethylsilyl)amide (3). This compound shows fluxionality on the NMR time scale due to a transannular trans–cis isomerization process and also a strong temperature dependency of the ratio of these two isomers. Variation of the stoichiometry allows the synthesis and isolation of homoleptic zinc bis(8-amidoquinoline) (4) with the zinc atoms in a distorted tetrahedral environment. The metallation of 8-aminoquinoline with (tmeda)NiMe2 yields diamagnetic nickel bis(8-amidoquinoline) (5) with a nickel center showing a distorted square planar coordination sphere. Dinuclear zinc complexes are accessible employing tetra-dentate di(8-aminoquinolyl)diphenylsilane (6). The metallation of 6 with dimethylzinc yields dimeric zinc di(8-amidoquinolyl)diphenylsilane (7) with tetrahedrally coordinated zinc atoms. A comparison of the molecular structures of 1a, 2b, 3, 4, 5, 6, and 7 shows nearly no dependency of the structural data of the quinolyl unit on the substitution pattern of the amino function. The metal–nitrogen bond lengths depend on the coordination numbers of the metal and the nitrogen atoms (terminal or bridging position) as well as the electrostatic attraction between the metal cations and the amino bases. [Copyright &y& Elsevier]

Abstract: The reaction of NaAs(H)SiiPr3 with ZnEt2 in the presence of additional triisopropylsilylarsane yields the heterobimetallic complex [(thf)Na]2 [(EtZn)6(AsSiiPr3)4] (1) in the shape of red prisms. The Na–As and Zn–As bond lengths show values of 301/309pm and between 247 and 260pm, respectively. [Copyright &y& Elsevier]