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A facile synthesis of 1H-indazoles featuring a Cu(OAc)2-catalyzed N-N bond formation using oxygen as the terminal oxidant is described. The reaction of readily available 2-aminobenzonitriles with various organometallic reagents led to o-aminoaryl N-H ketimine species. The subsequent Cu(OAc)2-catalyzed N-N bond formation in DMSO under oxygen afforded a wide variety of 1H-indazoles in good to excellent yields.

The novel ternary Zintl phase Li3NaGe2 is prepared by heating a stoichiometric mixture of the elements (Ta ampoule in evacuated silica tubes, 400 °C, 7 d; cooling at a rate of 0.5 °C/min).

In view of its potential use as anode material in Li ion batteries, Li12AgGe4 is discovered as the Li-richest phase in the ternary phase system.

Single crystals of Pd6.69Sn4.31 are obtained in attempts to grow ternary alloys in the system K—Pd—Sn (Nb crucible in evacuated silica tubes, 1.

Cs8-xGa8-ySi38+y (I) is obtained from a stoichiometric reaction of the elements in a CsCl flux, whereas K8Zn3.5Si42.5 (II) and Rb7.9Zn3.6Si42.4 (III) are prepared using a combined KBr or RbCl /Zn flux (alumina crucible sealed in stainless steel ampoule, 1173 K, 1 h; cooling to 923 K with a rate of 0.3 K/min).

NaP7 is prepared from stoichiometric quantities of red phosphorus and Na in the presence of purified CuI as mineralizer (evacuated graphitized silica tubes, 823 K, 7 d).

Mg0.39NiSn1.61 (I) and Mg2.61Ni4Sn3.39 (II) are prepared by melting of the elements (sealed Ta ampoules, 700 °C, 2 weeks).

Si nanoparticles are prepared by reaction of the Zintl phases Na4Si4, Rb7NaSi8, and M12Si17 (M: K, Rb, Cs) with NH4Br in DMF.

Single-phase samples of K8Al8Si38 (I), Rb8Al8Si38 (II), and Cs7.9Al7.9Si38.1 (III) clathrates are obtained by flux melting of Al/Si powder with an excess of Al and the respective alkali halide salt as the flux (alumina crucible in Nb ampoules, 1173 K, 1 h).

The intermetallic title compound is prepared by solid state reaction of the elements (Nb ampule, flowing Ar, 1223 K, 45 min) and characterized by powder and single crystal XRD, magnetic measurements, and TB-LMTO-ASA electronic structure calculations.

Single crystals of the new compounds K[K([2.2.2]crypt)]3[Co0.68@Sn9] (I) and [K([2.2.2]crypt)]5 [Co2@Sn17]·en·Tol (II) are prepared from solutions of K4.79Co0.79Sn9, and Kryptofix 222 in en and layered with toluene.

The title compound is synthesized from a stoichiometric mixture of the elements in the presence of CuCl2 as a mineralizer (silica ampule, 823 K, 7 d).

The title Zintl phases are prepared by reactions of the corresponding elemental alkali metals with pre-prepared M-Sn alloys (M: Ni, Co) at 550—880 °C for 48 h.

(III) crystallizes as black block-shaped crystals in the monoclinic space group C2/c with Z = 4 (single crystal XRD) and contains isolated, linear heteroatomic [Bi—Zn—Bi]4- anions.

High-level quantum chemical studies using periodic local-MP2 and dispersion-corrected density functional methods (DFT-B3LYP-D3) are performed to properly describe the dispersive host—guest interactions in noble gas filled Group 14 clathrates of type Ngx[M136] (Ng: Ar, Kr, Xe and M: Si, Ge, Sn).

The nature of the chemical bonds in the Zintl phase CaSi is investigated by a combined experimental and theoretical charge density analysis to test the validity of the Zintl-Klemm concept.

Dark blue crystals of K6[Bi4](NH3)8 are obtained from a solution of the Zintl phase KBi in liquid NH3 in the presence of 18-crown-6 (-70 °C, 3 months; 20-30% yield).

The new title compound is synthesized from a stoichiometric mixture of the constituent elements (tantalum ampule, 750 °C, 1 h) and characterized by single crystal XRD and magnetic measurements.

The detailed reinvestigation of the Li-rich part of the binary Li—Si phase diagram reveals the existence of Li4.106Si (Li16.42Si4) which forms through peritectic decomposition of the Li-richest phase Li17Si4 at 481—486 °C.

[K(18-crown-6)]2[Zn(Ge9)]·en is synthesized by reaction of K4Ge9 in en with Zn2{ [(2,4,6-Me3C6H2)NC(Me)] 2CH}2 in the presence of 18-crown-6 (25 °C, 12 h, yield given in g).

Large single crystals of K8Zn4Sn42 with a length of up to 6 mm are prepared from a mixture of the elements using excess Sn as a flux (Ta ampule, 650 °C, 1 h).

Two modifications of the new title compound, hP-Na2ZnSn5 (I) and tI-Na2ZnSn5 (II) are prepared from the elements at 450 and 300 °C, respectively.

Na4[Sn4]·13NH3 is obtained from deep red suspensions of Na4Sn4, Cu-Mst, and 18-crown-6 in liquid NH3 (-70 °C, 19 weeks, 25% yield).

MgNiGe (I), SrNiGe (II), and BaNiGe (III) are synthesized from equimolar ratios of the elements (sealed Ta tubes, 1.

CaFe2Si2 (I), CaFe0.68Rh1.32Si2 (II), CaRh2Si2 (III) and SrCo2Si2 (IV) are obtained from melts of the elements under Ar.

Single crystals of Li17Si4 are obtained from melts of the elements with 85—95 at.% Li and isolated by isothermal centrifugation.

In view of the search for alternative Li ion anode materials and electron-poor framework semiconductors for thermoelectric applications, Li3Zn2Sn4 and Li2ZnGe3 are obtained by solid state reaction of a stoichiometric mixture of the elements (Ta ampule in an evacuated silica tube, 500 °C and 700 °C for the Ge and Sn tetrelides, resp., 5 d).

Hygroscopic transparent single crystals of Cs8[Si6O16] are obtained by high-temperature reaction of Cs, Si, WO3, and HgO in the molar ratio of 5:5:1:1 (sealed Nb crucible in a fused silica tube, 1.

The crystal structures of Sm4Ir13Ge9 (I) and LaIr3Ge2 (II) are determined by single crystal XRD.

The title compound is prepared by arc melting of the elements followed by annealing (silica tube, Ar, 1050 °C, 24 h).

The new, isotypic compounds (IV) crystallize in the orthorhombic space group Pmn21 with Z = 2 (single crystal XRD).

The title compounds are prepared by arc-melting of the elements followed by annealing in welded Ta ampules (700—800 °C, 7—14 d).

Semitransparent dark-red or ruby-red single crystals of K10.35Ge18W0.65Nb0.35 O4, Rb10.35Ge18W0.65Nb0.35 O4, K10Ge18WO4, and Rb10Ge18WO4 are synthesized by solid state reactions using K, Rb, Ge, W, WO3, K2WO4, Rb2WO4, GeO2 and HgO as starting materials (Nb crucible, 800 °C, 120 h).