Hans Joachim Breunig

New developments in the chemistry of organoantimony and-bismuth rings

Novel organoantimony homocycles comprise a three-membered antimony ring, R3Sb3, organoantimony polycycles, R4Sb8, R5Sb7, and transition metal carbonyl complexes with the t-Bu4Sb4 or t-Bu3Sb4 ligand. In this review the use of t-Bu4Sb4 as a source for complexes with the Sb2 or cyclo-Sb3 ligands and the synthesis and characterisation of the first organobismuth monocycles, RnBin (n = 3, 4) are also discussed.

ORGANOANTIMONY COMPOUNDS WITH ELEMENT-ELEMENT BONDS

Abstract In this article an overview is given on recent developments in the chemistry of organometallic compounds with antimony—antimony bonds or bonds between antimony atoms and elements of the groups 14 and 16.

Organoantimony-containing polyoxometalate: [{PhSbOH}3(A-alpha-PW9O34)2]9-.

The dimeric, sandwich-type tungstophosphate [{PhSbOH}(3)(A-alpha-PW(9)O(34))(2)](9-) (1) has idealized D(3h) symmetry and represents the first organoantimony-containing polyoxometalate. Polyanion 1 was synthesized in an aqueous, acidic medium via three different routes and was fully characterized in the solid state by X-ray diffraction, IR, and thermogravimetric analysis and in solution by multinuclear NMR ((1)H, (13)C, (31)P, and (183)W).

Oxidation of tetraaryldistibanes: syntheses and crystal structures of diarylantimony oxides and peroxides, (R2Sb)2O, (R2Sb)4O6 and (R2SbO)4(O2)2 (R=Ph, o-Tol, p-Tol)

Abstract Tetraaryldistibanes, (R2Sb)2 (R=Ph, o-Tol, p-Tol) are synthesized by the reactions of R2SbNa with BrCH2CH2Br in liquid ammonia. They react with air oxygen to form (R2Sb)2O and (R2Sb)4O6. The reactions of (R2Sb)4O6 with H2O2 give peroxides, (R2SbO)4(O2)2. Single-crystal X-ray structure analyses reveal that the conformations of the (R2Sb)2O molecules are close to syn–syn (R=Ph) or to syn–anti (R=o-Tol, p-Tol). (Ph2SbO)4(O2)2 is an antimony-oxygen cluster with μ4-peroxo ligands.

Triphenyltelluronium derivatives of dithiophosphorus ligands: Crystal and molecular structure of [Ph3Te][S2PPh2] and [Ph3Te][(SPPh2)2N], displaying weak cation-anion Te…S secondary interactions

Abstract Triphenyltelluronium diphenylphosphinodithioate, [Ph 3 Te][S 2 PPh 2 ] ( 1 ) and tetraphenyldithioimidodiphosphinate, [Ph 3 Te][(SPPh 2 ) 2 N] ( 2 ), were obtained by metathesis reaction between Ph 3 TeCl and NH 4 [S 2 PPh 2 ] and K[(SPPh 2 ) 2 N], respectively, and were characterized by IR, MS and multinuclear NMR. The molecular structure of both compounds was investigated by X-ray diffractometry. The compounds are monomeric and predominantly ionic in the solid state. The Te…S interactomic distances (3.331 and 3.655 A in 1 , and 3.264 and 3.451 A in 2 indicate weak cation-anion secondary interactions. In both compounds the tellurium atom is five-coordinated, with distorted square-pyramidal geometry. The coordination polyhedron in 2 is less distorted due to the flexibility of the SPNPS system and the larger S…S bite of this ligand (4.276 A in 2 , vs 3.368 A in 1 ).

THE FIRST ORGANOBISMUTH RINGS : (RBI)3 AND (RBI)4, R = (ME3SI)2CH

Surprisingly facile at low temperatures is the synthesis of the first cyclobismuthanes 1 and 2 [Eq. (1)]. In solution 1 and 2 are in equilibrium. The four-membered ring 2 forms black crystals, which were structurally analyzed. At room temperature the rings decompose to elemental bismuth and R3 Bi. R=(Me3 Si)2 CH.

Strukturen von [Me4Sb]2[MeSbI4]MeSbI2, und [Me4Sb]I. Darstellung von Me3Sb · MeSbI2 und farbwechsel bei Me4Sb2 · Me2SbBr

Abstract The crystal structures of the complex [Me 4 Sb] 2 [MeSbI 4 ] ( 1 ) and its precursors MeSbI 2 ( 2 ) and [Me 4 Sb]I ( 3 ) are reported. In 1 there are tetrahedral cations and square pyramidal anions with Sb-I distances of 290–320 pm. The structure of 2 contains MeSbI 2 molecules. They associate via iodine bridges to form linear chains with alternating short and long Sb-I distances. The coordination around antimony is distorted tetragonal pyramidal. The tetrahedral coordination of the ions in 3 results in the formation of a wurtzite type structure with antimony-iodine distances of 406 and 435 pm. The novel adducts Me 3 Sb·Me 2 SbI 2 ( 4 ) and Me 2 SbSbMe 2 ·Me 2 SbBr ( 5 ) are formed by reaction of the components. They decompose easily with formation of antimony(V) compounds. Crystals of 5 are yellow but become reversibly black on cooling.

Synthesis and Biological Activity of Organoantimony(III)-Containing Heteropolytungstates

Three discrete organoantimony(III)-containing heteropolytungstates [(PhSb(III))(4)(A-α-Ge(IV)W(9)O(34))(2)](12-) (1), [(PhSb(III))(4)(A-α-P(V)W(9)O(34))(2)](10-) (2), and [{2-(Me(2)NCH(2)C(6)H(4))Sb(III)}(3)(B-α-As(III)W(9)O(33))](3-) (3) have been synthesized in one-pot reactions in aqueous medium using the appropriate lacunary heteropolyanion precursor and organoantimony(III) source. Polyanions 1-3 were isolated as hydrated salts, (NH(4))(12)[(PhSb(III))(4)(A-α-Ge(IV)W(9)O(34))(2)]·20H(2)O (1a), Rb(9)Na[(PhSb(III))(4)(A-α-P(V)W(9)O(34))(2)]·20H(2)O (2a), and Rb(3)[{2-(Me(2)NCH(2)C(6)H(4))Sb(III)}(3)(B-α-As(III)W(9)O(33))]·7H(2)O (3a). The compounds 1a-3a were fully characterized in the solid state using infrared (IR) spectroscopy, single-crystal XRD, and thermogravimetric and elemental analyses. The stability of 1-3 in aqueous solution was confirmed by multinuclear NMR ((1)H, (13)C, (31)P, and (183)W) spectroscopy. Preliminary studies on the biological activity of 1-3 showed that all three compounds might act as potent antimicrobial agents.

Syntheses and structures of dimesitylbismuth(III) bromide, Mes2BiBr, and bis(diphenyldithiophosphinato)mesitylbismuth(III), MesBi(S2PPh2)2

Addition of BiBr3 to Mes3Bi (Mes = 2, 4, 6-Me3C6H2) in Et2O gives 86% of Mes2BiBr (1) as yellow crystals. Reaction of 1 with Ph2PS2NH4 in a 1 : 1 molar ratio gives a quantitative yield of MesBi(S2PPh2)2 (2) rather than the expected dimesitylbismuth compound. The crystal and molecular structures of 1 and 2 were determined at 153 K and 173 K, respectively. They contain Mes2BiBr molecules with trigonal pyramidal coordination around Bi. The mean BiC bond distance is 2.27 A and the BiBr bond distance is 2.690(2) A. The angles around Bi vary between 89.4 and 106.4°. Intermolecular Bi…Br contacts of 3.795 A, indicating weak secondary bonding, give rise to zig-zag shaped (BiBr)x chains. In the polymeric chain the coordination geometry around bismuth atoms can be described as pseudo-trigonal bipyramidal. The crystals of 2 consist of discrete monomeric MesBi(S2PPh2)2 molecules with a symmetry plane containing the metal atom and the aromatic ring of the attached mesityl group. The dithiophosphinato ligands exhibit an anisobidentate coordination pattern with long and short phosphorus—sulfur bonds, i.e. P(1)S(1) 2.051(31) A and P(1)S(2) 1.980(3) A, related to short and long bismuth—sulfur distances, respectively, i.e. BiS(1) 2.662(2) A and BiS(2) 3.123(3) A. This leads to a square-pyramidal geometry around the bismuth atom, with the metal lying 0.33 A above the basal plane formed by the four sulfur atoms.

Strukturen und Reaktionen von Methylantimondihalogeniden und Versuche zur Darstellung von Methylantimon

Abstract MeSbCl 2 ( 1 ) and SbCl 3 give the adduct MeSbCl 2 ·0.6SbCl 3 ( 1a ). MeSbBr 2 ( 2 ) reacts with NaI to form MeSbI 2 ( 3 ) and with Cr(CO) 5 THF to give Me(Br) 2 SbCr(CO) 5 ( 4 ). The crystal structures of 1a , 2 and 4 are reported. Derivatives of methyl antimony are obtained by reaction of 2 or 4 with Mg in tetrahydrofuran.