Formation of Metal Clusters or Nitrogen-Bridged Adducts by Reaction of a Bis(amino)stannylene with Halides of Two-Valent Transition Metals
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- 作者：Michael Veith ; Alice Mü ; ller ; Lothar Stahl ; Martin Nö ; tzel ; Maria Jarczyk ; and Volker Huch
- 刊名：Inorganic Chemistry
- 出版年：1996
- 出版时间：June 19, 1996
- 年：1996
- 卷：35
- 期：13
- 页码：3848 - 3855
- 全文大小：231K
- 年卷期：v.35,no.13(June 19, 1996)
- ISSN：1520-510X
文摘
When the cyclic bis(amino)stannyleneMe2Si(NtBu)2Sn is allowed to reactwith metal halides MX2 (M = Cr, Fe,Co, Zn; X = Cl, Br [Zn]) adducts of the general formula[Me2Si(NtBu)2Sn·MX2]nare obtained. The compoundsare generally dimeric (n = 2) except the ZnBr2 adduct,which is monomeric in benzene. The crystal structuresof[Me2Si(NtBu)2Sn·CoCl2]2(triclinic, space group 
ntities/Pmacr.gif">1; a =8.620(9) Å, b = 9.160(9) Å, c =12.280(9) Å, 
=101.2(1)ntities/deg.gif">, 
= 97.6(1)ntities/deg.gif">, 
= 105.9(1)ntities/deg.gif">, Z= 1) and of[Me2Si(NtBu)2Sn·ZnCl2]2(monoclinic, space groupP21/c;a = 8.156(9) Å, b = 16.835(12) Å,c = 13.206(9) Å, = 94.27(6)ntities/deg.gif">,Z = 2) were determined by X-ray diffractiontechniques. The two compounds form similar polycyclic,centrosymmetrical assemblies of metal atoms bridgedby chlorine or nitrogen atoms. While in the case of the cobaltcompound Co is pentacoordinated by three chlorineand two nitrogen atoms, in the zinc derivative Zn is almosttetrahedrally coordinated by three chlorine atoms andone nitrogen atom. The iron derivative[Me2Si(NtBu)2Sn·FeCl2]2seems to be isostructural with the cobaltcompound as can be deduced from the crystal data (triclinic,a = 8.622(7) Å, b = 9.158(8) Å,c = 12.353(8) Å, = 101.8(1)ntities/deg.gif">, = 96.9(1)ntities/deg.gif">, =105.9(1)ntities/deg.gif">, Z = 1). If NiBr2,PdCl2, or PtCl2 is combined with thestannylene,the reaction product is totally different: 4 equiv of the stannyleneare coordinating per metal halide, forming themolecular compound[Me2Si(NtBu)2Sn]4MX2,which crystallizes with half a mole of benzene per molecularformula.The crystal structures of[Me2Si(NtBu)2Sn]4·NiBr2·1/2C6H6(tetragonal, space group I41/a,a = b = 43.86(4) Å,c = 14.32(2) Å, Z = 16) and[Me2Si(NtBu)2Sn]4·PdCl2·1/2C6H6(tetragonal, space group I41/a,a = b = 43.99(4)Å, c = 14.318(14) Å, Z = 16) revealthe two compounds to be isostructural. The molecules have an innerSn4Mpentametallic core (mean distances: Sn-Ni 2.463 Å, Sn-Pd 2.544Å) with the transition metal in the center ofa slightly distorted square formed by the four tin atoms, thedistortion from planarity resulting in a weakparamagnetism of 0.2 ntities/mgr.gif">B for the nickel compound. Thehalogen atoms form bridges between two of the tinatoms and have no bonding interaction with the transition metal.The nickel compound has also been preparedby direct interaction of Br2 orNR4Br3 with[Me2Si(NtBu)2Sn]4Ni asa minor product, the main products beingMe2Si(NtBu)2Sn(NtBu)2SiMe2,Me2Si(NtBu)2SnBr2,NiBr2 and SnBr2. Other metal clusters havebeen obtainedby the reaction of Me2Si(NtBu)2Snwith tetrakis(triphenyphosphine)palladium or by the reactionof Me2Si(NtBu)2Gewith RhCl(PPh3)3. In the first casePh3PPd[Sn(NtBu)2SiMe2]3PdPPh3(rhombohedral, space group R3c, a =b =21.397(12) Å, c = 57.01(5) Å, = =90ntities/deg.gif">, = 120ntities/deg.gif">, Z = 12) is formed and ischaracterized by X-ray techniquesto be composed of a central PdSn3Pd trigonal bipyramidwith the tin atoms occupying the equatorial positions(Pd-Sn = 2.702(5) Å). In the second reaction all thetriphenylphosphine ligands are replaced from rhodium andRh[Ge(NtBu)2SiMe2]4Clis formed (monoclinic, space groupP21/n, a =12.164(2) Å, b = 23.625(5) Å, c=24.128(5) Å, = 102.74(3)ntities/deg.gif">, Z = 4).The central core of this molecule is made up of a rhodium atomwhich isalmost square planarly coordinated by the germanium atoms, two of whichare bridged by chlorine (mean Ge-Rh = 2.355 Å).
ntities/Pmacr.gif">1; a =8.620(9) Å, b = 9.160(9) Å, c =12.280(9) Å, =101.2(1)ntities/deg.gif">, = 97.6(1)ntities/deg.gif">, = 105.9(1)ntities/deg.gif">, Z= 1) and of[Me2Si(NtBu)2Sn·ZnCl2]2(monoclinic, space groupP21/c;a = 8.156(9) Å, b = 16.835(12) Å,c = 13.206(9) Å, = 94.27(6)ntities/deg.gif">,Z = 2) were determined by X-ray diffractiontechniques. The two compounds form similar polycyclic,centrosymmetrical assemblies of metal atoms bridgedby chlorine or nitrogen atoms. While in the case of the cobaltcompound Co is pentacoordinated by three chlorineand two nitrogen atoms, in the zinc derivative Zn is almosttetrahedrally coordinated by three chlorine atoms andone nitrogen atom. The iron derivative[Me2Si(NtBu)2Sn·FeCl2]2seems to be isostructural with the cobaltcompound as can be deduced from the crystal data (triclinic,a = 8.622(7) Å, b = 9.158(8) Å,c = 12.353(8) Å, = 101.8(1)ntities/deg.gif">, = 96.9(1)ntities/deg.gif">, =105.9(1)ntities/deg.gif">, Z = 1). If NiBr2,PdCl2, or PtCl2 is combined with thestannylene,the reaction product is totally different: 4 equiv of the stannyleneare coordinating per metal halide, forming themolecular compound[Me2Si(NtBu)2Sn]4MX2,which crystallizes with half a mole of benzene per molecularformula.The crystal structures of[Me2Si(NtBu)2Sn]4·NiBr2·1/2C6H6(tetragonal, space group I41/a,a = b = 43.86(4) Å,c = 14.32(2) Å, Z = 16) and[Me2Si(NtBu)2Sn]4·PdCl2·1/2C6H6(tetragonal, space group I41/a,a = b = 43.99(4)Å, c = 14.318(14) Å, Z = 16) revealthe two compounds to be isostructural. The molecules have an innerSn4Mpentametallic core (mean distances: Sn-Ni 2.463 Å, Sn-Pd 2.544Å) with the transition metal in the center ofa slightly distorted square formed by the four tin atoms, thedistortion from planarity resulting in a weakparamagnetism of 0.2 ntities/mgr.gif">B for the nickel compound. Thehalogen atoms form bridges between two of the tinatoms and have no bonding interaction with the transition metal.The nickel compound has also been preparedby direct interaction of Br2 orNR4Br3 with[Me2Si(NtBu)2Sn]4Ni asa minor product, the main products beingMe2Si(NtBu)2Sn(NtBu)2SiMe2,Me2Si(NtBu)2SnBr2,NiBr2 and SnBr2. Other metal clusters havebeen obtainedby the reaction of Me2Si(NtBu)2Snwith tetrakis(triphenyphosphine)palladium or by the reactionof Me2Si(NtBu)2Gewith RhCl(PPh3)3. In the first casePh3PPd[Sn(NtBu)2SiMe2]3PdPPh3(rhombohedral, space group R3c, a =b =21.397(12) Å, c = 57.01(5) Å, = =90ntities/deg.gif">, = 120ntities/deg.gif">, Z = 12) is formed and ischaracterized by X-ray techniquesto be composed of a central PdSn3Pd trigonal bipyramidwith the tin atoms occupying the equatorial positions(Pd-Sn = 2.702(5) Å). In the second reaction all thetriphenylphosphine ligands are replaced from rhodium andRh[Ge(NtBu)2SiMe2]4Clis formed (monoclinic, space groupP21/n, a =12.164(2) Å, b = 23.625(5) Å, c=24.128(5) Å, = 102.74(3)ntities/deg.gif">, Z = 4).The central core of this molecule is made up of a rhodium atomwhich isalmost square planarly coordinated by the germanium atoms, two of whichare bridged by chlorine (mean Ge-Rh = 2.355 Å).