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Calixarene Complexes (calixarene + complex)
Selected AbstractsSynthesis and X-Ray Crystal Structures of the First Antimony and Bismuth Calixarene Complexes.CHEMINFORM, Issue 45 2004Lihua Liu No abstract is available for this article. [source] Iron(III) and Zinc(II) Calixarene Complexes: Synthesis, Structural Studies, and Use as Procatalysts for ,-Caprolactone PolymerizationCHEMISTRY - AN ASIAN JOURNAL, Issue 3 2010Abdessamad Arbaoui Dr. Abstract Treatment of the heterobimetallic iron(II) alkoxides [(THF)MFe(OtBu)3]2 with p - tert -butylcalix[4]areneH4 (L1H4) affords the oxo-bridged diiron(III) complexes {Fe[M(NCMe)x]2L1}2(,-O), M=Na, x=2 1,8(CH3CN), M=,K, x=3 2,3.5(CH3CN); similar use of p - tert -butylcalix[6]areneH6 (L2H6) afforded [{Fe2(,-O)Na2(OH2)(NCMe)2L2}2][{Fe2(,-O)Na(OH2)(NCMe)6L2}2]2,[Na(NCMe)5]22+3,9.46(CH3CN) and [{Fe2(,-O)L2(K(NCMe)2)2}2] 4,10.8(MeCN), respectively. In the case of 4, a minor product {(L22Fe8O8)[K(NCMe)1.5K(H2O)(NCMe)2.5]2} 5,6(CH3CN), which is comprised of chains of (L22Fe8O8) clusters bridged by K/MeCN fragments, is also isolated. Use of p - tert -butylcalix[8]areneH8 (L3H8) and two equivalents of [(THF)KFe(OtBu)3]2 affords [(K2(,-NCCH3)4(,-OH2))2(Fe2(,-O)L3H2)2(CH3CN)2] 6,9(CH3CN). In the case of p - tert -butyltetrahomodioxacalix[6]areneH6 (L4H6), reaction with [(THF)MFe(OtBu)3]2 (two equivalents) leads to isolation of the pseudoisomorphic complexes [M2(CH3CN)4L4Fe2(,-O)].4CH3CN M=Na 7,4(CH3CN), M=K 8,2(CH3CN); similar use of p - tert -butylhexahomotrioxacalix[3]areneH3 (L5H3) led to [Na2Fe2(,-OH)2(L5)2(CH3CN)4] 9,2(CH2Cl2). The complex [L4(ZnEt)4Zn2(CH3CN)4(,-OEt)2], 10,2(CH3CN), isolated from the reaction of L4H6 and ZnEt2 is also reported. Complexes 1,10 are structurally characterized (partially in the case of 4) and screened (not 5) as catalysts for the ring opening polymerization of ,-caprolactone. [source] Two related lithium calixarene complexes, [p-tert -butylcalix[4]arene(OMe)(OH)2(OLi)]2·4MeCN and {p-tert -butylcalix[4]arene(OH)2(OLi)[OLi(NCMe)2]}2·8MeCN, determined using synchrotron radiationACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2009Darren S. Lee The crystal structures of acetonitrile solvates of two related lithium calixarene complexes have been determined by low-temperature single-crystal X-ray diffraction using synchrotron radiation. Bis(,-5,11,17,23-tetra- tert -butyl-26,28-dihydroxy-25-methoxy-27-oxidocalix[4]arene)dilithium(I) acetonitrile tetrasolvate, [Li2(C45H57O4)2]·4C2H3N or [p-tert -butylcalix[4]arene(OMe)(OH)2(OLi)]2·4MeCN, (I), crystallizes with the complex across a centre of symmetry and with four molecules of unbound acetonitrile of crystallization per complex. Tetraacetonitrilebis(,-5,11,17,23-tetra- tert -butyl-26,28-dihydroxy-25,27-dioxidocalix[4]arene)tetralithium(I) acetonitrile octasolvate, [Li4(C44H54O4)2(C2H3N)4]·8C2H3N or {p-tert -butylcalix[4]arene(OH)2(OLi)[OLi(NCMe)2]}2·8MeCN, (II), also crystallizes with the complex lying across a centre of symmetry and contains eight molecules of unbound acetonitrile per complex plus four more directly bound to two of the lithium ions, two on each ion. The cores of both complexes are partially supported by O,H...O hydrogen bonds. The methoxy methyl groups in (I) prevent the binding of any more than two Li+ ions, while the corresponding two O-atom sites in (II) bind an extra Li+ ion each, making four in total. The calixarene cone adopts an undistorted cone conformation in (I), but an elliptical one in (II). [source] | ||||||||||