| Under the protection of purified water-free, oxygen-free argon, Using Schlenk techniques, Reaction of {[(C13H8)CH2SiMe2(NH)CMe3]Li2(THF -)x} with LnCl3 in THF resulted in four new Complexes Ln[(n5-C,3H8)CH2SiMe2(1-N)CMe3(THF)(u-Cl)]2-2THF, [Ln=Pr(1), Gd (2), Y(3), Er(4)]. All complexes were determined by X-ray diffraction: (1) was monoclinic system, Space group P21/n, a=11.1456(14)A, b=18.270(2)A,c=15.694(2)A,p=106.719(2),V=3060.7(7)A3,u=1.741mm -1, z=3, R=0.0368, Rw=0.1232,Gof=1.072 . (2) was monoclinic system space group P2,/n, a=11.1749(2)A, b= 18.0889(4)A, c=15.66160(10)A, B=106.8370(10),V=3030.15(9)A3, M=2.339mm-1, z=4, R=0.0562, Rw=0.1384,Gof=1.155. (3) was monoclinic system Space group P21/n, a=11.18360(10)A, b=17.9584(4)A, c= 15.6348(3)A, B=106.9640(10), V=3003.46(9)A3, M=2.098mm-1, z=4, R=0.0969, Rw=0.2336,Gof=1.134. (4) was monoclinic system space group P21/n, a=ll. 1636(10) A, b=17.8696(6)A, c=15.5748(14)A, 0=106.9770(10), V=2971.3(5)A3, M= 2.978mm-1, z=2, R=0.0319, Rw=0.1044,Gof=1.067. These complexes are soluble in polar organic solvents such as THF, ether, slightly soluble in toluene and n-hexane. Each of them possesses a crystallographic inversion center at the heterochiral dimmer. In the centrosymmetric molecule ,each Ln3+ ion is 5-bond to one cyclopentadienyl ring in fluorenyl and o-bond to one oxygen atom of THF, one N atom, and two doubly bridging Cl atoms in a distorted-pyramidal arrangement.The formal coordination number for each Ln is seven. They are of the very rare structurally characterized examples of organolanthanide compounds (CGC) bearing both Ln-C n and c-bond and Ln-Cl bonds.In order to compare, we synthesized another amido-fluorenyl organolanthanide containing a shorter -SiMe2- link. Unexpectedly weobtained a new Er complex, in which the ether decomposed. Its molecular structure was determined by X-ray diffraction. This complex was triclinic system Space group P-1, a=12.01240(10)A, b=12.4199(2)A, c=15.0573 (2)A, P=68.4120(10),V=1867.62(4)A3, M=4.540mm-1, z=2, R=0.0620, Rw=0.1309,Gof=1.176.The complex is a centrosymmetric cluster containing two IVOH units. Each of the two Ms-OH atoms coordinates to three Er atoms in a tetrahedral geometry. These tetrahedrons share one edge to form the core structure of the cluster Each of the two Er atoms on the common edge coordinates to two Hs-OH, two doubly bridging ^ -OEt atoms, and one triply bridging Ms-OEt atoms. Each of the other two Er atoms is 1-bound to one fluorenyl ring and 1-bound to one N atom and two M3-OH, two doubly bridging JV-OEt atoms, and one triply bridging JVQEt atoms. Each of the two Li atoms coordinates to two doubly bridging Mj-OEt atoms, and one triply bridging ^-OEt atoms, and one O atom in the THF molecule.During synthesis of containing -CH2SiMe2- bridge amido-fluorenyl organolanthanide, we also found the LnCl3(Ln=Nd, Yb) did not give the very organolanthanide, but further the new amido-fluorenyl ligand to come into being in moderate yielding.. It crystallizes in monoclinic spaceGroup p-1 with unit cell parameters: a=11.4627(4) A, b=11.7574(3)A, c=14.6222(10)A, B=67.0770(10),V=1832.76(9)A3, u=0.126mm-1, z=2, R=0.0721, Rw=0.l406,Gof=1.067. X-ray diffraction analysis reveals this compound is a bis-1,1 ' -amido-fluorenyl ligand.
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