33654_07b

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: ar anions are embedded between columns of condensed icosahedra (Cs6K612)~+ which in turn are centred by the remaining unique monatomic Sb3- anion. Inl IM04O0627 prepared The indium by heating the appropriate mixture Of In, Mo and Moo2 at liOO.C, features novel quasilinear chain cations. Ins7+ and in channels M . SOMER, . PETERS, . POPP nd H. G . VON SCHNERING, K T a Z . anorg. allg. Chem. 597, 201-8 (1991). Ch. 7 between condensed clusters of M06 octahedra.(66) The intrachain distances are 262-266pm in In57+ and 265-269pm in In68+, which are the shortest known In-In interatomic distances cf. 325 and 337pm in In metal itself, and 333 pm for the closest distances between In atoms in neighbouring chains in the molybdate. Interatomic angles within the chains are 158” and 163” respectively and, when the coordination around each In atom by contiguous In and 0 atoms is considered, the chains can be formulated as [ ~ n ~ + ( ~ n + ) , ~ nn + ] , 3, 4. ’= Square-pyramidal 5-coordinate In”’ occurs in certain organoindium compounds such as the bis(2-methylaminopyridino-) adduct [MeIn{MeNC(CH)4N2](67) cf. InC1S2- (p. 238). The less familiar pentagonal planar coordination has been established for the InMnS group in the dianion [(p5-In){Mn(CO)4}5]2- which is readily prepared by treatment of InC13 with the manganese carbonyl cluster compound K3[Mn3(p-CO)2(CO)lo].(68) mean Mn-Mn The distance in the encircling plane-pentagonal “ligand” (Mn(CO),Js is 317 pm; the mean In-Mn distance is 265pm, and the In atom is only 4.6pm from the best plane of the five Mn atoms. Note also that the ligand is isolobal with cyclopentadienyl, C5H5. Seven-coordinate pentagonal-bipyramidal In”’ has been found in the chloroindium complex of 1,4,7-triazacyclononanetriacetic acid - [{-(CH,),~(CH,COZH)}~], (LH3).(69) The neutral, monoprotonated 7-coordinate complex [InCI(LH)] features C1 and one N in axial positions (angle Cl-In-N 168”) with the other two N atoms and three carboxylate 0 atoms in the pentagonal plane. Interest in such compounds stems 66 H . MAITAUSCH,A. SIMON and E.-M. PETERS, Inorg. Chem. 25, 3 428-33 (1986). 67 A . M. A ~D. ~ B~ , ~D. M . F N ~M ,~B , HURST~ , ~ HOUSE and B . HUSSAIN, . Chem. SOC., Chem. Commun., J 7 83-4 (1985). 68 M . SCHOLLENBERGER,NUBER and M. L. ZIEGLER, B. Angew. Chem. Znf. Edn. Engl. 3 1, 350-1 (1992). 6 9A. S . CRAIG, I . M. HELPS, D. PARKER, H. ADAMS, N. A . BAILEY, M. G. WILLIAMS, J . M . A. SMITH and G . FERGUSON, Polyhedron 8, 2 481-4 (1989). c. ~ ~ 257 Organometallic compounds 9.. 736 (a) (b) Figure 7.18 (a) 1,4,7,10-tetraazacyclododecanetriacetic acid, (LH3). (b) Structure of the 7-coordinate complex [InL]; the coordination polyhedron (shown in white) comprises a trigonal prism of 4N and 2 0 capped on one of its quadrilateral faces by the third 0 atom. from the use of the y-active "'In isotope ( E , 173, 247 keV, t l p 2.81 d) in radio-labelled monoclonal antibodies to detect tumours. Interestingly, the 7-coordinate crystalline complex reverts to a stable neutral hexacoordinate species in aqu...
View Full Document

This note was uploaded on 10/12/2012 for the course CHEMISTRY CHM1040 taught by Professor Jhon during the Spring '12 term at Florida A&M.

Ask a homework question - tutors are online