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Organooxotin cages, clusters and coordination polymers containing Sn-O units were assembled by the reactions of organotin precursors with phosphonic, phosphinic, carboxylic or sulfonic acids. These assemblies contain a central stannoxane core and a functional periphery which can be readily modulated to assemble photoactive, electroactive or multisite coordinating molecules.

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]

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]

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]

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]

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]

Two new iron(III)-potassium phosphonate cage complexes with {K(2)Fe(6)} and {K(2)Fe(4)} cores are reported. Magnetic studies reveal antiferromagnetic interactions between the Fe(III) centres occur in these cages.

The reaction of the phosphorus trihydrazide, (S)P[N(Me)-NH(2)](3) (1) with quinoline-2-carboxaldehyde (C(9)H(6)N-2-CHO) in a 1:3 ratio afforded a trishydrazone, (S)P[N(Me)-N=CH-2-C(9)H(6)N](3) (2). Crystals of 2 were grown in three different solvent media affording an unsolvated (2, monoclinic, P2(1)/n) and two solvated (2·3H(2)O, trigonal, R3 and 2·2CH(3)OH, triclinic, P ̅1) 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 2 with Ag(ClO(4))(2)·6H(2)O in methanol afforded a dinuclear cationic cage [Ag{(S)P[N(Me)-N=CH-2-C(9)H(6)N](3)}·ClO(4)](2) (3). The molecular structure of 3 reveals a dimeric structure consisting of two Ag(I) ions that are held together by two ligands. Only two arms of the tris hydrazone ligand are involved in coordination while an unprecedented P=S→Ag(I) coordination is seen. This results in the formation of an Ag(2)S(2) dimer that is encapsulated by two trishydrazone ligands. Both compounds 2 and 3 are photoluminescent., (This journal is © The Royal Society of Chemistry 2011)

The synthesis and structure of a novel decanuclear copper(II) cage is reported. The assembly of the cage is facilitated by the cumulative coordinative interaction of tert-butyl phosphonate, 2-pyridylpyrazole and hydroxide ligands with copper(II) ions. Magnetic studies of this decanuclear copper(II) cage indicate complex antiferromagnetic behaviour.

Organostannoxane-based multiredox assemblies containing ferrocenyl peripheries have been readily synthesized by a simple one-pot synthesis, either by a solution method or by room-temperature solid-state synthesis, in nearly quantitative yields. The number of ferrocenyl units in the multiredox assembly is readily varied by stoichiometric control as well as by the choice of the organotin precursors. Thus, the reaction of the diorganotin oxides, R2SnO (R = Ph, nBu and tBu) with ferrocene carboxylic acid affords tetra-, di-, and mononuclear derivatives [{Ph2Sn[OC(O)Fc]2}2] (1), [{[nBu2SnOC(O)Fc]2O}2] (2), [nBu2Sn{OC(O)Fc}2] (3), [{tBu2Sn(OH)OC(O)Fc}2] (4), and [tBu2Sn{OC(O)Fc}2] (5) (Fc = eta(5)C5H4-Fe-eta(5)C5H5). The reaction of triorganotin oxides, R3SnOSnR3 (R = nBu and Ph) with ferrocene carboxylic acid leads to the formation of the mono-nuclear derivatives [Ph3SnOC(O)Fc] (6) and [{nBu3SnOC(O)Fc}(n)] (7). Molecular structures of the compounds 1-4 and 6 have been determined by single-crystal X-ray analysis. The molecular structure of compound 1 is new among organotin carboxylates. In this compound, ferrocenyl carboxylates are involved in both chelating and bridging coordination modes to the tin atoms to form an eight-membered cyclic structure. In all of these compounds, the acidic protons of the cyclopentadienyl groups are hydrogen bonded to the carboxylate oxygens (C-HO) to form rich supramolecular assemblies. In addition to this, pi-pi, T-shaped, L-shaped, and side-to-face stacking interactions involving ferrocenyl groups also occur. Compound 6 shows an interesting and novel intermolecular CO2-pi stacking interaction. Electrochemical analysis of the compounds 1-4, 6, and 7 shows a single, quasi-reversible oxidation peak corresponding to the simultaneous oxidation of four, two, and one ferrocenyl substituents, respectively. Compound 5 shows two quasi-reversible oxidation peaks. This is attributed to the positional difference among the ferrocenyl substituents on the tin atom. Additionally, while compounds 2 and 4 are electrochemically quite robust and do not decompose even after ten continuous CV cycles, compounds 1, and 3, 5-7 start to show decomposition after five cycles.

A 1:2 reaction of Ph3SnOSnPh3 1 with RfCOOH 2 leads to the formation of [Ph2Sn(OH)OC(O)(Rf)]2 3, by means of a facile Sn-C bond cleavage process.