| The synthesis and properties of dicarba-closo-dode-caboranes were first reported at the end of 1963 in both the United States and the USSR. Their chemistry is one of the most complete in the field of boranes and heteroboranes. One of the most striking features of the carborane is the capability of the 2 carbon atom and 10 boron atoms to adopt the icosahedral geometry in which the carbon and boron atoms are hexacoordinate. This feature of the icosahedral structure gives rise to the unusual properties of such molecules and their carbon and boron derivatives.The use of carborane clusters has been directed toward broadening of their applications in organometallic chemistry, pharmaceutical chemistry, and materials science, such as molecular recognition systems, display devices, modular construction systems, nonlinear optical (NLO) materials, special polymers, and olefin polymerization catalysts.This dissertation describes the synthesis and structural characterization of organometallic complexes with 1,2-dichalcogenolato-1,2-dicarba-closo-dodecaborane (12) (E2C2B10H10, E = S, Se) ligands, with emphasis being placed on two fields. One is the synthesis of those complexes containing metal-metal bond, the other is the building of multi-cluster complexes.In the dissertation, ninety complexes were synthesized, which containing 7,2-dichalcogenolato-1,2-dicarba-closo-dodecaborane ligand, and sixty-eight complexes were determined through X-ray single crystal diffraction analysis.This dissertation consists of listed contents:(1) The reaction of [Cp*IrCl2]2(Cp* =η5-C5Me5) with dilithium- 1, 2- dicarba- closo-dodecaborane(12) -1,2-dithiolate or -diselenolate afforded the 16-electron iridium(III) half-sandwich complexes Cp*Ir[E2C2(B10H10)] [E = S (1a), Se (1b)]. The molecular geometry of la(lb) were determined by X-ray structural analysis. The metallacycle defined by [Ir(1), S(1), S(2), C(1), C(2)] or [Ir(1), Se(1), Se(2), C(1), C(2)] in 1a(1b) is nearly planar and perpendicular to the Cp* ring. A series of trinuclear clusters {Cp*Ir[E2C2(B10H10)]}2Mo(CO)2 (E = S (6a), Se (6b)), {Cp*Ir[E2C2(B10H10)]}2 W(CO)2 (E = S (8a), Se (8b)), containing Ir-Mo, Ir-W metal-metal bond were obtained from the reaction of la(lb) with [Mo(CO)3(py)3] or [W(CO)3(py)3]in the presence of BF3·OEt2. Their structures have been determined by X-ray crystallography. Some of complexes' third-order nonlinear optical (NLO) properties have been investigated by Z-scan technique. The results indicate that 6a exhibit good NLO absorption and self-focusing effects. The hyperpolarizabilityγvalue is calculated to be 2.60×10-29 esu for 6a.(2) The 16-electron half-sandwich iridium complexes 1a(1b) reacted with Co2(CO)8 in toluene to afford the trinuclear cluster complexes [Cp*Ir{E2C2(B10H10)}]{Co2(CO)5} [E = S(11a), Se(11b)] and mononuclear carbonyl complexes [Cp*Ir(CO){E2C2(B10H10)}] [E = S(7a), Se(7b)] as by-products respectively. Complexes 11a, 11b were found to consist of close IrCo2 triangle geometry with two Ir-Co bonds and one Co-Co bond. The binuclear IrFe complexes [Cp*Ir{E2C2(B10H10)}]{Fe(CO)3} [E = S(12a), Se(12b)] were obtained from the reaction of 1a, 1b with Fe(CO)5 and 2 equiv of Me3NO. The molecular structures of 11a, 11b, 12b have been determined by X-ray crystallography.(3) The reaction of Cp*M[E2C2(B10H10)] (M = Rh, Ir; E = S, Se) with [Rh(cod)(μ-Cl)]2 (cod = cyclo-octa-1,5-diene, C8H12) give a series of trinuclear cluster: 17a, 18a, 19a, 20a, 22a, which containing Ir2Rh, Rh3 core. The metal-metal bonds are bridged by dithiolate or diselenolate ligand E2C2(B10H10)2-. Through the formation of trans-{Cp*Ir[S2C2(B10H9)]}Rh{[S2C2(B10H10)]IrCp*} (22a), we studied the theory from mononuclear, dinuclear cluster to trinuclear cluster.(4) The novel tetrametallic cluster complexes {Cp*Ir[E2C2(B10H9)]}Rh2(cod) {Cp*Ir[E2C2(B10H10)]} (E = S(24a); Se(24b)) have been synthesized by reactions of the 16-electron half-sandwich iridium complexes [Cp*Ir{E2C2(B10H10)}] [E = S(1a), Se(1b)] with [Rh(cod)(μ-OEt)2] at room temperature in toluene solution. In the solid state, this tetrametallic cluster exhibits an irregular nearly planar metal skeleton with the two carborane dichalcogenolato ligands bridging the four metal centers from the both side of the tetrametallic plane. Even though all metal atoms coordinate bridging chalcogen atoms, they show different electronic and coordination environments.(5) Dimetallic complexes {Cp*Ir[E2C2(B9H9)][(cod)Ir(OCH3)]} [E=S(33a), E=Se, (33b)], {Cp*Ir[E2C2(B10H9)][(cod)Ir]} [E=S(34a), E=Se(34b)] were synthesized by the reaction of Cp*Ir[E2C2(B10H10)] [E = S(1a), Se(1b)] with 2 equivalents of [Ir(cod)(μ-OMe)]2 (2-Ir). Analogous reaction of la with [Rh(cod)(μ-OMe)]2 (2-Rh) were investigated and three complexes {Cp*Ir[S2C2(B9H9)][(cod)Rh(OCH3)]} (35a), {Cp*Ir[S2C2(B10H10)][(cod)Rh]} (36a), {Cp*Ir[S2C2(B10H9)][(cod)Rh]} (21a) were obtained. By comparing with the two reaction, the routes of metal induced B-H activation at the B(3)/B(6) of ortho-carborane-1,2-dichalcogenolato ligand were investigated. These nido-carborane complexes such as 33a, 33b, 35a, 35b contain intercluster metal-metal bonds. Moreover, the V-shaped trimetallic unit {(cod)Ir[E2C2(B9H8)][(cod)Ir(OCH3)][(C8H13)Ir]} [E = S(38a), Se(38b)] have been constructed through the M2-nido-carborane complexes{(cod)Ir[E2C2(B9H9)][(cod)Ir(OCH3)]} [E = S(37a), Se(37b)]. X-ray structural analyses were studied for complexes 33a, 33b, 34a, 35a, 36a, 37a, 38b and 39b. (6) Base on the rule of addition reaction at the metal center of Cp*M[E2C2(B15H10)], multicluster molecule [Cp*MS2C2(B10H10)]n(L) (M = Rh, Ir) [n = 2, 3, 4] which connected with pyridyl-based ligands, were prepared and characterized by X-ray crystallography. Through the changing of ligand, different kind of multi-nuclear complexes were synthesised, such as complexes 43-54 and tirnuclear supramolecular compelxes 55-57. Moreover, the assembly of soluble, air-stable, porphyrin-carborane supramolecular structure {(Zn-TPyP)[Cp*fr{S2C2(B10H10)}]4(THF)2} (60), {(Zn-TPyP) [Cp*Ir{S2C2(B10H10)}]2-6(CHCl3)}n (61), based on metal-containing moieties [Cp*Ir{S2C2(B10H10)}] (la) bridged by nitrogen-based organic spacers are built by the same method.
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