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The reaction of bis(tri- n-butyltin)oxide, [ nBu3Sn]2O, with HO2C-C6H4-4-CF3 (RfTol-CO2H) affords a coordination polymer [ nBu3SnO2C-RfTol] n ( 1). 1 undergoes hydrolysis in the presence of atmospheric moisture, at room temperature, resulting in the formation of the diorgano stannoxane [{ nBu2SnO2C-RfTol}2O]2 ( 2). The transformation of 1 to 2 is accompanied by a Sn-C bond cleavage reaction. Formation of 2 also occurs in a direct reaction, involving [ nBu3Sn]2O and RfTol-CO2H in the presence of water. 2 can also be prepared in a 1:1 reaction of di- n-butyltin oxide, [ nBu2SnO] n with RfTol-CO2H. The conversion of 2 from 1 was monitored by 119Sn NMR spectroscopy over a period of eight days. The molecular structure of 2 reveals a tetranuclear assembly consisting of two pairs of structurally distinct six-coordinate tin atoms. Extensive hydrogen-bonding interactions (C-H ···O, C-H ···F) and weak F ···F interactions involving organo-fluorine atoms in the crystal structure result in the formation of a three-dimensional supramolecular architecture for 2. [ABSTRACT FROM AUTHOR]

Three new Cu–Ln cage complexes bridged by phosphonates and acetates are reported; one—a Cu24Dy8cage—is a new single molecule magnet (SMM). [ABSTRACT FROM AUTHOR]

Phosphonate ligands, [RPO3]2-, are extremely versatile in the assembly of multi-tin and multi-copper architectures. We have used organostannoxane cores for supporting multi-ferrocene and multi-porphyrin peripheries. The copper-metalated multi-porphyrin compound is an excellent reagent for facile cleavage of DNA, even in the absence of a co-oxidant. Reaction of t-BuPO3H2 with Cu(ClO4)2. 6H2O in the presence of 2-pyridylpyrazole (2-Pypz) leads to the synthesis of a decanuclear copper (II) assembly. [ABSTRACT FROM AUTHOR]

The reaction of n-BuSn(O)(OH) with various substituted benzoic acids affords hexameric organostannoxane drums, [n-BuSn(O)OC(O)R]6, where R = 2,6-(CH3)2−C6H3 (1), 4-CH3−C6H4 (2), 4-NH2−C6H4 (3) and 2-NH2−C6H4 (4). The central stannoxane motif (Sn6O6) is similar in all these compounds and is surrounded by six substituted benzoate groups. All the drums show an extensive supramolecular organization in the solid state. Accordingly, drum 1 forms a one-dimensional supramolecular assembly mediated by noncovalent interactions such as C−H···O and π···π interactions. Similarly, drums 2−4 form interesting three-dimensional supramolecular assemblies mediated by C−H···O, N−H···N, C−H···π, and π···π interactions in the solid state. The role of the peripheral aromatic substituents in determining the final course of the supramolecular assembly is discussed. This article describes the synthesis and structural characterization of the hexameric organooxotin cages [n-BuSn(O)OC(O)R]6, where R = 2,6-(CH3)2−C6H3, 4-CH3−C6H4, 4-NH2−C6H4, and 2-NH2−C6H4, also known as drums. All the drums show an extensive supramolecular organization mediated by intermolecular interactions (C−H···O, N−H···N, C−H···π, and π···π) in the solid state. [ABSTRACT FROM AUTHOR]

Abstract: Organooxotin compounds can be assembled by using various synthetic methodologies. Although in most instances, organotin oxides and hydroxides are the preferred starting materials for preparing organooxotin compounds, Sneavage reactions involving organotin compounds also offer a rational route. This review deals with the recent progress in this area and examines various reactions, where Sne occurs. A wide range of products are accessible from this approach and these are presented in this article. [Copyright &y& Elsevier]

An efficient one-pot protocol for the synthesis of multi-substituted 2-pyrone derivatives from internal alkynes and unactivated alkenes is reported. The methodology involves difunctionalization of internal alkynes by using Pd(II) as a catalyst alongwith X-Phos as ligand via 6- endo transesterification and subsequent alkenylation pathway. Notable features include simple and easily available starting materials, including a range of unactivated alkenes, reduced synthetic steps and mild reaction conditions with high efficiency. [ABSTRACT FROM AUTHOR]

The reaction of MnCl2·4H2O with t-BuPO3H2 in the presence of triethylamine afforded the tridecanuclear cage, [MnIIMnIII 12(μ4-O)6(μ-OH)6(O3P–t-Bu)10(OH2)2(DMF)4]·[2MeOH·4DMF] (1). The structural analysis of 1 reveals that it is a mixed-valent complex containing a [MnIIMnIII 12(μ4-O)6] core. The centre of the core is occupied by a MnII ion which is surrounded by 12 MnIII ions. The latter are connected to each other by six μ-OH− and 10 t-BuPO3 2− ligands. The vacant coordination sites of six MnIII ions situated in the periphery are occupied by four DMF and two water molecules. Magnetic studies on 1 reveal a frequency-dependent response which is characteristic of single-molecule magnets. [ABSTRACT FROM AUTHOR]

A series of diorganotin complexes of dithiocarbamates[Sn(C4H9)2(S2CN(RR′)2)2] (R, R′ = ethyl (1); R =methyl, R′ = butyl (2); R, R′ = butyl (3); R = methyl, R′ = hexyl (4); and [Sn(C6H5)2(S2CN(RR′)2)2] (R, R′ = ethyl (5); R =methyl, R′ = butyl (6); R, R′ = butyl (7); R = methyl, R′ = hexyl (8) were synthesized.Single-crystal X-ray structures of 2, 3,and 8were determined. Thermogravimetric analysis (TGA)showed single-step decomposition for the complexes 1, 3, and 5–8, and double-stepdecomposition for the complexes 2and 4between195 °C and 325 °C. Complexes 1–4were used as single-source precursors for the depositionof SnS thin films by aerosol-assisted chemical vapor deposition (AACVD)at temperatures from 400 °C to 530 °C. Orthorhombic SnSthin films were deposited from all four complexes at all depositiontemperatures. The films were characterized by UV–vis spectroscopy,powder X-ray diffraction (p-XRD), Raman spectroscopy, scanning electronmicroscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), andalso electrical resistivity measurements. [ABSTRACT FROM AUTHOR]

N, N′-dioxide ligands such as 2, 2′-bipyridine- N, N-dioxide (BPDO-I) and 4, 4′-bipyridine- N, N-dioxide (BPDO-II) were used to trap the hydrated dimethyltin cations under controlled hydrolysis. The use of the chelating ligand BPDO-I leads to the isolation of the discrete monocation [Me2Sn(BPDO-I)(OH2)(NO3)]+[NO3]- ( 2), whereas the linear ligand BPDO-II directs the construction of cationic polymers, [{Me2Sn(OH2)2(μ-BPDO-II)}2+{NO3-}2 ·2H2O] n ( 3·2H2O) and [{Me2Sn(μ-OH)(BPDO-II)}22+{NO3-}2 ·H2O] n ( 4·H2O) under different reaction conditions. [ABSTRACT FROM AUTHOR]

The reaction of the phosphorus trihydrazide, (S)P[N(Me)-NH2]3(1) with quinoline-2-carboxaldehyde (C9H6N-2-CHO) in a 1 : 3 ratio afforded a trishydrazone, (S)P[N(Me)-NCH-2-C9H6N]3(2). Crystals of 2were grown in three different solvent media affording an unsolvated (2, monoclinic, P21/n) and two solvated (2·3H2O, trigonal, R3 and 2·2CH3OH, triclinic, P1) crystal forms. Each of these, while possessing an essentially similar molecular structure, adopt different crystal packing giving rise to supramolecular structures mediated by a variety of weak interactions: O–H–N, O–H–O, C–H–N, C–H–O, C–H–S, C–H–π, π–π, N–π and S–π. The reaction of 2with Ag(ClO4)2·6H2O in methanol afforded a dinuclear cationic cage [Ag{(S)P[N(Me)-NCH-2-C9H6N]3}·ClO4]2(3). The molecular structure of 3reveals a dimeric structure consisting of two AgIions that are held together by two ligands. Only two arms of the tris hydrazone ligand are involved in coordination while an unprecedented PS→AgIcoordination is seen. This results in the formation of an Ag2S2dimer that is encapsulated by two trishydrazone ligands. Both compounds 2and 3are photoluminescent. [ABSTRACT FROM AUTHOR]

A ruthenium catalyzed intramolecular C-S coupling reaction of N-arylthioureas for the synthesis of 2-aminobenzothiazoles has been developed. Kinetic, isotope labeling, and computational studies reveal the involvement of an electrophilic ruthenation pathway instead of a direct C-H activation. Stereoelectronic effect of meta-substituents on the N-arylthiourea dictates the final regioselective outcome of the reaction. [ABSTRACT FROM AUTHOR]

Thereactions of 3-(N9-adeninyl) propanoic acid (LH) with various di- andtriorganotin oxides have been investigated. Thus, the reaction of di-tert-butyltin oxide (t-Bu2SnO)3in a 3:1 ratio afforded the dinuclear derivative [t-Bu2Sn(μ-OH)L]2·7H2O (1). A similar reaction involving bis(tri-n-butyltin)oxide, (n-Bu3Sn)2O, in a 2:1 ratio afforded the one-dimensional (1D) coordinationpolymer [n-Bu3SnL·0.33H2O]n(2). Similarly the reactionwith (n-Bu2SnO)nin a 2:1 ratio afforded the tetranuclear [{n-Bu2Sn}2(μ3-O)(μ-OH)L]2(3). On the other hand, asimilar reaction in a 1:1 ratio also gave the tetranuclear product[{n-Bu2Sn}2(μ3-O)L2]2(4). The molecular structureof 1reveals a central dinuclear Sn2O2motif where the two tin centers are bridged by two μ-OHgroups. Each tin is bound with a monodentate carboxylate group; theCO unit of these carboxylates is involved in an intramolecularhydrogen bonding with the bridging OH unit. The supramolecular structureof 1reveals the formation of a 1D zigzag chain mediatedby intermolecular hydrogen bonding interaction through the Watson-Crickor the Hoogsteen faces. 2is a 1D coordination polymerformed by the successive bridging of triorganotin units by the carboxylateligand L. The supramolecular structure of 2reveals thattwo 1D coordination polymers interact to generate novel adenine homotrimersformed as a result of alternating Watson-Crick–Watson-Crickand Hoogsteen–Watson-Crick interactions. The molecular structuresof 3and 4reveal them to be tetranuclearpossessing a ladder-like structure. The essential difference betweentheir molecular structures is that in 4there are fourcarboxylate ligands, while in 3there are only two. Bothof these complexes reveal intramolecular and intermolecular hydrogenbonding and π···π stacking interactions.The nematicidal activity of 1–3 wasexamined against Caenorhabditis elegans. Compound 2was found to be highly active, effecting a high mortalityeven at very low concentrations such as 25 or 10 ppm. [ABSTRACT FROM AUTHOR]

A multicomponent synthetic strategy involving copper(II) ions, tert-butylphosphonic acid (t-BuPO3H2) and 3-substituted pyrazole ligands has been adopted for the synthesis of soluble molecular copper(II) phosphonates. The use of six different 3-substituted pyrazoles, 3-R-PzH [R = H, Me, CF3, Ph, 2-pyridyl (2-Py), and 2-methoxyphenyl (2-MeO-C6H4)] as ancillary ligands afforded nine different decanuclear cages, [Cu5(μ3-OH)2(O3P-t-Bu)3(3-R-Pz)2(X)2]2·(Y) where R = H, X = t-BuPO3H, and Y = (Et3NH+)4(solvent) (1); R = Me, X = 3-MePzH, and Y = solvent (2); R = Me, X = t-BuPO3H, and Y = (Et3NH+)4(solvent) (3); R = CF3, X = t-BuPO3H, and Y = (Et3NH+)4(solvent) (4); R = Ph, X = 3-PhPzH, and Y = solvent (5); R = 2-Py, X = 0.5 MeOH, and Y = solvent (6); R = 2-Py, X = none, and Y = solvent (7); R = 2-Py, X = H2O, and Y = (Et3NH+·PF6-)2(solvent) (8); R = 2-MeO-C6H4, X = MeOH or 0.5:0.5 MeOH/H2O, and Y = solvent (9). Compounds 1-6, 8, and 9 were isolated using a direct synthetic method which involves the reaction of copper(II) salts and the ligands, while 7 was obtained from an indirect route involving the reaction of preformed copper-pyridylpyrazolate precursor complexes and t-BuPO3H2. The decametallic compounds 1-9 possess a butterfly shaped core. The core of the cages 1, 3, and 4 are tetraanionic and contain more phosphonates than pyrazole ligands, while the other cages are neutral and contain more pyrazoles than phosphonate ligands. Compounds 1-6 have been studied by electrospray ionization-high-resolution mass spectrometry (ESI-HRMS). The decanuclear cage 6 was shown to be a good plasmid modifier. [ABSTRACT FROM AUTHOR]

Abstract: Various phosphorus-supported fluorescent probes have been synthesized by the condensation reaction of multi-functional phosphorus hydrazides with various fluorophore-containing carboxaldehydes. Compounds, thus prepared, in this study are (PhO)2P(O)[N(Me)–N;R] (1a, 1b), Ph2P(O)[N(Me)–N;R] (2b, 2c, 2d), PhP(O)[N(Me)–N;R]2 (3b, 3c), P(S)[N(Me)–N;R]3 (4b, 4c), P(O)[N(Me)–N;R]3 (5a, 5b, 5c), N3P3(O2C12H8)2[N(Me)–N;R]2 (6a, 6b, 6c), N3P3(O2C12H8)[N(Me)–N;R]4 (7a, 7b, 7c, 7d) and N3P3[N(Me)–N;R]6 (8b, 8c), where R=1-pyrenyl (a), 9-anthracenyl (b), 9-phenanthryl (c) and 7-(N,N′-diethylamino)-3-coumarinyl (d). All of these compounds have been characterized by various analytical techniques including 31P{1H} NMR spectroscopy. Compounds 1b, 2b, 3b, 4b, 5b, 5c and 6d have also been characterized by single crystal X-ray analysis. All of these phosphorus-supported compounds exhibit excellent fluorescence properties in aqueous solution at near physiological conditions. [Copyright &y& Elsevier]

The article presents chemical equation for the article "Solvent-Free Multicomponent Synthesis of Biologically-Active Fused-Imidazo Heterocycles Catalyzed by Reusable Yb(OTf)3 Under Microwave Irradiation" by A. Ansari and others, published in the journal "ChemistrySelect" in 2016.

Kinetic, isotope labeling, and computational studies reveal the involvement of an electrophilic ruthenation pathway instead of a direct C-H activation for this reaction. [ABSTRACT FROM AUTHOR]