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Ullazines and their π-expanded derivatives have gained much attention as active components in various applications, such as in organic photovoltaic cells or as photosensitizers for CO2 photoreduction. Here, we report the divergent synthesis of functionalized diazaullazines by means of two different domino-reactions consisting of either a Povarov/cycloisomerization or alkyne–carbonyl metathesis/cycloisomerization protocol. The corresponding quinolino-diazaullazine and benzoyl-diazaullazine derivatives were obtained in moderate to good yields. Their optical and electronic properties were studied and compared to related, literature-known compounds to obtain insights into the impact of nitrogen doping and π-expansion. [ABSTRACT FROM AUTHOR]

The reaction of Li[[Mes.sup.*]NH] (1, [Mes.sup.*] = 2,4,6-tri-tert-butylphenyl) with aminoarsane [Mes.sup.*]N(H)As[Cl.sub.2] (2, [Mes.sup.*] = 2,4,6-t-[Bu.sub.3][C.sub.6][H.sub.2]) at -80 [degrees]C resulted in the formation of bisamino(chloro)arsane [([Mes.sup.*]NH).sub.2]AsCl (3Cl) by elimination of LiCl. 3Cl reacted with the Lewis acids such as Al[Cl.sub.3], Ga[Cl.sub.3], and Ag[X] (X = As[F.sub.6.sup.-], OT[f.sup.-], B[F.sub.4.sup.-]; OTf = trifluoromethanesulfonate = OS[O.sub.2]C[F.sub.3.sup.-]) upon chloride ion abstraction to give salts bearing the cation [[[([Mes.sup.*]NH).sub.2]As].sup.+] (3[X]; X = As[F.sub.6.sup.-], OT[f.sup.-], B[F.sub.4.sup.-], E[Cl.sub.4]; E = Al, Ga). [3.sup.+] represents the first NH-functionalized acyclic bis(amino)arsenium cation. The formation of the salts bearing [3.sup.+] could also be observed in the reaction of cyclo-1, 3-diarsa-2, 4-diazane [[ClAs([mu]-N[Mes.sup.*])].sub.2] (4) with Lewis acids (Al[Cl.sub.3], Ga[Cl.sub.3]) in the presence of proton sources in solution. All presented salts 3[X] were stable at room temperature and fully characterized. Key words: arsenic, cation, bis(amino)arsenium cation, crystal structure. La réaction du Li[[Mes.sup.*]NH] (1, [Mes.sup.*] = 2,4,6-tri-tert-butylphényl) avec l'aminoarsane [Mes.sup.*]N(H)As[Cl.sub.2] (2, [Mes.sup.*] = 2,4,6-t-[Bu.sub.3][C.sub.6][H.sub.2]) à -80 [degrees]C a donné lieu à la formation du bisamino(chloro)arsane [([Mes.sup.*]NH).sub.2]AsCl (3Cl) par élimination du LiCl. Le 3Cl a réagi avec des acides de Lewis tels que l'Al[Cl.sub.3], le Ga[Cl.sub.3] et l'Ag[X] (X = As[F.sub.6.sup.-], OT[f.sup.-], B[F.sub.4.sup.-]; OTf = trifluorométhanesulfonate = OS[O.sub.2]C[F.sub.3.sup.-]) par abstraction de l'ion chlorure pour former des sels comportant le cation [[[([Mes.sup.*]NH).sub.2]As].sup.+] (3[X]; X = As[F.sub.6.sup.-], OT[f.sup.-], B[F.sub.4.sup.-], E[Cl.sub.4]; E = Al, Ga). L'ion [3.sup.+] représente le premier cation bis(amino)arsénium cyclique fonctionnalisé par un groupe NH. Nous avons pu également observer la formation de sels comportant l'ion [3.sup.+] lors de la réaction du cyclo-1,3-diarsa-2,4-diazane [[ClAs([mu]-N[Mes.sup.*])].sub.2] (4) avec des acides de Lewis (Al[Cl.sub.3], Ga[Cl.sub.3]) en solution en présence d'une source de protons. Tous les sels 3[X] présentés se sont révélés stables à température ambiante et ont été soumis à une caractérisation complète. [Traduit par la Rédaction] Mots-clés: arsenic, cation, cation bis(amino)arsénium, structure cristalline., Introduction In the last decades, the possibility to generate dicoordinate nitrogen bound arsenic compounds was shown not only for a series of amino(imino)arsanes (I, Scheme 1), but also for non-cyclic [...]

A new synthetic route to 1H-1,2,3-triazole-4,5-dithiols (tazdtH2) as ligands for the coordination of NiII, PdII, PtII and CoIII via the dithiolate unit is presented. Different N-protective groups were introduced with the corresponding azide via a click-like copper-catalyzed azide-alkyne [3 + 2] cycloaddition (CuAAC) and fully characterized by NMR spectroscopy. Possible isomers were isolated and an alternative synthetic route was investigated and discussed. After removal of the benzyl protective groups on sulfur by in situ-generated sodium naphthalide, complexes at the [(dppe)M] (M = Ni, Pd, Pt), [(PPh3)2Pt] and [(η5-C5H5)Co] moieties were prepared and structurally characterized by XRD analysis. In this process, the by-products 11 and 12 as monothiolate derivatives were isolated and structurally characterized as well. With regioselective coordination via the dithiolate unit, the electronic influence of different metals or protective groups at N was investigated and compared spectroscopically by means of UV/Vis spectroscopy and cyclic voltammetry. Complex [(η5-C5H5)Co(5c)] (10), is subject to a dimerization equilibrium, which was investigated by temperature-dependent NMR and UV/Vis spectroscopy (solution and solid-state). The thermodynamic parameters of the monomer/dimer equilibrium were derived. [ABSTRACT FROM AUTHOR]

The palladium(0)-catalyzed Suzuki cross-coupling reaction of the bis(triflates) of methyl 2,5-dihydroxybenzoate and methyl 2,4-dihydroxybenzoate afforded para- and meta-terphenyls, respectively. The reactions proceeded with very good site selectivity in favor of the sterically less hindered carbon atom. Key words: terphenyls, cross-coupling, palladium, site selectivity, Suzuki reaction. La reaction de couplage croise de Susuki des bis(triflates) de methyl 2,5-dihydroxybenzoate et de methyl 2, 4-dihydroxybenzoate catalysee au palladium(O) a donne les para-et meta-terphenyles, respectivement. Les reactions se sont deroulees avec une tres bonne selectivite de site en faveur de l'atome de carbone steriquement le moins encombre. [Traduit par la Redaction] Mots-cles: terphenyles, couplage croise, palladium, selectivite de site, reaction de Suzuki., Introduction Functionalized p-terphenyls occur in a great variety of pharmacologically relevant natural products. Examples include terphenyllin, (1) terprenin, (2) curtisian A, (3) leucomentin- (6,4) thelephorin A, (5) ganbajunin D, (6) [...]

This article provides the first single-crystal XRD-based structure of enantiopure (R)-baclofen (form C), C10H12ClNO2, without any co-crystallized substances. In the enantiopure title compound, the molecules arrange themselves in an orthorhombic crystal structure (space group P212121). In the crystal, strong hydrogen bonds and C--H...Cl bonds interconnect the zwitterionic molecules. [ABSTRACT FROM AUTHOR]

Within the second funding period of the SPP 1708 "Material Synthesis near Room Temperature",which started in 2017, we were able to synthesize novel anionic species utilizing Ionic Liquids (ILs) both, as reaction media and reactant. ILs, bearing the decomposable and non‐innocent methyl carbonate anion [CO3Me]−, served as starting material and enabled facile access to pseudohalide salts by reaction with Me3Si−X (X=CN, N3, OCN, SCN). Starting with the synthesized Room temperature Ionic Liquid (RT‐IL) [nBu3MeN][B(OMe)3(CN)], we were able to crystallize the double salt [nBu3MeN]2[B(OMe)3(CN)](CN). Furthermore, we studied the reaction of [WCC]SCN and [WCC]CN (WCC=weakly coordinating cation) with their corresponding protic acids HX (X=SCN, CN), which resulted in formation of [H(NCS)2]− and the temperature labile solvate anions [CN(HCN)n]− (n=2, 3). In addition, the highly labile anionic HCN solvates were obtained from [PPN]X ([PPN]=μ‐nitridobis(triphenylphosphonium), X=N3, OCN, SCN and OCP) and HCN. Crystals of [PPN][X(HCN)3] (X=N3, OCN) and [PPN][SCN(HCN)2] were obtained when the crystallization was carried out at low temperatures. Interestingly, reaction of [PPN]OCP with HCN was noticed, which led to the formation of [P(CN)2]−, crystallizing as HCN disolvate [PPN][P(CN⋅HCN)2]. Furthermore, we were able to isolate the novel cyanido(halido) silicate dianions of the type [SiCl0.78(CN)5.22]2− and [SiF(CN)5]2− and the hexa‐substituted [Si(CN)6]2− by temperature controlled halide/cyanide exchange reactions. By facile neutralization reactions with the non‐innocent cation of [Et3HN]2[Si(CN)6] with MOH (M=Li, K), Li2[Si(CN)6] ⋅ 2 H2O and K2[Si(CN)6] were obtained, which form three dimensional coordination polymers. From salt metathesis processes of M2[Si(CN)6] with different imidazolium bromides, we were able to isolate new imidazolium salts and the ionic liquid [BMIm]2[Si(CN)6]. When reacting [Mes(nBu)Im]2[Si(CN)6] with an excess of the strong Lewis acid B(C6F5)3, the voluminous adduct anion {Si[CN⋅B(C6F5)3]6}2− was obtained. [ABSTRACT FROM AUTHOR]

The [Me.sub.3]SiOTf-mediated condensation of 1-ethoxy-2-fluoro-1,3-bis(trimethylsilyloxy) 1,3-dienes with 3-cyanochromones to generate 3-cyano-2-(4-ethoxy-3-fluoro-2,4-dioxobutyl)chroman-4-ones is described. The product distribution in the reaction depends on the structure of the diene and the formation of the biaryls is demonstrated by an unprecedented domino 'retro-Michael/aldol/fragmentation' reaction.