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Abstract: The intramolecularly coordinated heteroleptic stannylene [4-t-Bu-2,6-{P(O)(O-i-Pr)2}2C6H2]SnCl serves as synthon for the synthesis of the ferrocenyl-bridged bis(diorganostannylene) [4-t-Bu-2,6-{P(O)(O-i-Pr)2}2C6H2SnC5H4]2Fe (1) which in turn reacts with W(CO)6 and Cr(CO)4(C7H8) to provide the corresponding transition metal complexes [4-t-Bu-2,6-{P(O)(O-i-Pr)2}2C6H2Sn{W(CO)5}C5H4]2Fe (2) and [4-t-Bu-2,6-{P(O)(O-i-Pr)2}2C6H2SnC5H4]2Fe·Cr(CO)4 (3), respectively. Reaction of compound 1 with sulphur and atmospheric moisture gave, under partial tin–carbon and oxygen–carbon bond cleavage, a tetranuclear organotin-oxothio cluster 5. All compounds were characterized by 1H, 13C, 31P, and 119Sn NMR, and IR spectroscopy, as well as by single-crystal X-ray diffraction analysis. Compounds 1 and 3 were also investigated by Mössbauer spectroscopy. Cyclovoltametric studies reveal the influence of the organostannyl moieties on the redox-behaviour of compounds 1–3 in comparison with unsubstituted ferrocene. [Copyright &y& Elsevier]

Abstract: The synthesis and molecular structure of [2,6-(t-BuOCH2)2C6H3Sn(OH)]2O (2), the only second example of a monomeric tetraorganodistannoxane, is reported. Compound 2 crystallizes in two polymorphic modifications (2a, monoclinic; 2b, triclinic). The two modifications especially differ in their intramolecular Sn⋯Odistances which fall in the range between 2.789(3) and 3.194(5) Å. It appears, that both the latter and intramolecular O⋯H–O bridges (2.882(4)–2.907(6) Å) contribute to the stability of the monomeric structures. [Copyright &y& Elsevier]

Abstract: Reaction between bis(chlorodiphenylstanyl)methane and the sodium salt of 2-hydroxypyridine (pyONa) in the molar ratio of 1:2 provides the organotin hydroxide derivative [Ph2(pyO)SnCH2Sn(OH)Ph2]2 (1) (where pyO=anion of 2-hydroxypyridine), while reaction of bis(dibromophenylstanyl)methane with the sodium salt of pyrimidine-2-thione (pmtNa) in molar ratio of 1:4 gives the corresponding organotin thiolate derivative, as its toluene solvate [BrPh(pmt)Sn]2CH2 ·C7H8 (2) (where pmt=anion of pyrimidine-2-thione). Both compounds were characterized by single crystal X-ray diffraction analysis and contain five-coordinate tin atoms. Compound 1 is a centrosymmetric head-to-tail dimmer with almost symmetrical Sn(1)–O(H)–Sn(2A) bridges. [Copyright &y& Elsevier]

The bismuth halides BiX3 (X=Cl, Br, I) react with the chelating oxygen-coordinating-donor ligand (iso-PrO)2(O)PCH2P(O)(Oiso-Pr)2 (L) to give one-to-one complexes, which have been characterised by single crystal X-ray-diffraction, IR spectroscopy, thermal analysis, NMR-spectroscopy, electrospray ionisation mass spectrometry (ESI MS) and conductivity measurements. In the solid state the complexes [BiX3L]2 (1, X=Cl; 2, X=Br; 3, X=I) show a dimeric bi-octahedral structure. Thermolysis analyses show that amorphous bismuth phosphonates are formed when the bulk material is heated to temperatures in the range 160–180 °C. The liberation of iso-PrX (X=Cl, Br, I) and propene is observed in this temperature range. The solid state structures are not retained in solution and electrospray ionisation mass spectrometry of CH3CN solutions of 1–3 revealed the presence of compounds such as [(iso-PrO)2(O)PCH2P(O)(Oiso-Pr)2H]+, [BiX2L2]+ and [BiX4]− (X=Cl, Br, I). [Copyright &y& Elsevier]

Abstract: The pentacyclic spirotryprostatin scaffold embodies an oxindole with an all-carbon quaternary stereocenter. The scaffold can efficiently be accessed in a one-pot reaction sequence consisting of a highly enantioselective 1,3-dipolar cycloaddition, N-acylation of the resulting stereochemically complex 3,3′-pyrrolidinyl-spirooxindole core with Fmoc-proline and spontaneous ring closure upon N-deprotection. [Copyright &y& Elsevier]

The novel triphosphonic ester 1,3,5-[P(O)(i-PrO)2]3C6H3 (1) was synthesized and fully characterized including single crystal X-ray diffraction analysis. Crystallization in the presence of CHCl3 gave the corresponding solvate, 1·CHCl3, which shows moderate C–H⋯OP hydrogen bonding. The hydrogen bond strength in 1·CHCl3 and the model compound [P(O)(i-PrO)2]C6H5·CHCl3 (2·CHCl3) were analyzed using RHF, DFT and MP2 methods. The calculated C–H⋯OP hydrogen bond strength is in the range 5–6 kcal mol-1, which is comparable with hydrogen bond strength in the water dimer but higher than in comparable C–H⋯OC aggregates. [Copyright &y& Elsevier]

Five new organotin(IV) molecules with the heterocyclic thioamides; 2-mercaptobenzothiazole (Hmbzt), 5-chloro-2-mercaptobenzothiazole (Hcmbzt), 3-methyl-2-mercaptobenzothiazole (mmbzt) and 2-mercaptonicotinic acid (H2mna) of formulae [(n-C4H9)2Sn(mbzt)2] (1), [(C6H5)2Sn(mbzt)2] (2), {(CH3)2Sn(cmbzt)2]·1.7(H2O)} (3), [(n-C4H9)2SnCl2(mmbzt)2·(CH2Cl2)] (4) and {[(C6H5)3Sn]2(mna)·[(CH3)2CO]} (5) have been synthesized and characterized by elemental analysis, 1H-, 13C-NMR, FT-IR and Mo¨ssbauer spectroscopic techniques. Crystal structures of molecules 1, 3 and 5 have been determined by X-ray diffraction at 173(1) K (1 and 5) and 293(2) K (3). Compound 1 C22H26N2S4Sn, is monoclinic, space group C2/c, a=44.018(2), b=8.8864(5), c=12.8633(7) A˚, β=104.195(5)°, Z=8. Compound 3 is also monoclinic, space group P21/c and a=17.128(2) A˚, b=17.919(2) A˚, c=7.3580(10) A˚, β=98.290(10)°, Z=4. In both molecules 1 and 3, two carbon atoms from aryl groups, two sulfur and two nitrogen atoms from thione ligands form a distorted octahedral geometry around tin(IV) with trans-C2, cis-N2, cis-S2 configurations. Compound 5 C45H39NO3SSn2 is monoclinic, space group P21/n, a=9.1148(2) A˚, b=29.2819(6), c=15.5556(4) A˚, β=106.2851(9)°, Z=4. Complex 5 contains two [(C6H5)3Sn(IV)] moieties linked by a double deprotonated 2-mercaptonicotinic acid (H2mna). Both tin(IV) ions are five coordinated. This complex is the an example of a pentacoordinated Ph3SnXY system with an axial-equatorial arrangement of the phenyl groups at Sn(1) atom. Compounds 1, 3 and 5 were tested for in vitro cytotoxicity against the cancer cell line of sarcoma cells (mesenchymal tissue) from the Wistar rat, polycyclic aromatic hydrocarbons (benzo[a]pyrene) carcinogenesis. Compound 5 exhibits strong cytotoxic activity, while complexes 1 and 3 show less cytotoxic activity. [Copyright &y& Elsevier]