title: Tetrathiomolybdate Complexes of Rhodium(I) with Molybdenum-Rhodium Interactions.
abstract: The synthesis and characterization of the tetrathiomolybdatorhodium(I) monoanionic complexes [L2Rh(μ-S)2MoS2](-) (L = CO (3), P(OPh)3 (4), P(O-o-Tol)3 (P(o-CH3C6H4)3; 5), P(OMe)3 (6), P(OEt)3 (7), P(O-i-Pr)3 (8); L2 = COD (1,5-cyclooctadiene; 2), cis-dppen (cis-Ph2PCH═CHPPh2; 9), dppe (Ph2PCH2CH2PPh2; 10), dppb (Ph2P(CH2)4PPh2; 11)) is presented. The complex 2 (NEt4(+) salt) was characterized by X-ray diffraction analysis. A detailed DFT study of the electronic structures of 2-4 and 6-8 has revealed the existence of extended electron delocalization over the four-membered Rh(μ-S)2Mo ring and hence the possibility of electronic communication between the metal centers. The electronic spectra were studied with TDDFT calculations, and the main absorption band in the visible region was assigned to ν(Rh→Mo) electron transfer transition, which is actually a HOMO-LUMO transition. The ν(Rh→Mo) transition was found to correlate linearly both with Tolman's electronic parameter of the phosphite ligands and the calculated HOMO-LUMO gap of the complexes, rendering it a well-defined ligand electronic parameter, which describes the net donating ability of monodentate and bidentate ligands (CO, COD, phosphites, diphosphines). The study of the variation of Δδ((31)P) and (1)J(Rh-P) of the phosphite complexes with respect to the QALE model electronic parameters χd, πp, and Ear has succeeded in the assessment of the σ and π effects on these NMR spectral parameters.
authors.affiliation: Faculty of Chemistry, National and Kapodistrian University of Athens , 15771 Athens, Greece.
authors.forename: Nikoletta
authors.initials: N
authors.lastname: Xamonaki
authors.affiliation: Faculty of Chemistry, National and Kapodistrian University of Athens , 15771 Athens, Greece.
authors.forename: Anastasios
authors.initials: A
authors.lastname: Asimakopoulos
authors.affiliation: Faculty of Chemistry, National and Kapodistrian University of Athens , 15771 Athens, Greece.
authors.forename: Anastasios
authors.initials: A
authors.lastname: Balafas
authors.affiliation: Faculty of Chemistry, National and Kapodistrian University of Athens , 15771 Athens, Greece.
authors.forename: Marilena
authors.initials: M
authors.lastname: Dasenaki
authors.affiliation: Faculty of Chemistry, National and Kapodistrian University of Athens , 15771 Athens, Greece.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Choinopoulos
authors.affiliation: IU/CINQUIMA, Quı́mica Inorgánica, Facultad de Ciencias, Universitad de Valladolid , 47071 Valladolid, Spain.
authors.forename: Silverio
authors.initials: S
authors.lastname: Coco
authors.affiliation: Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation , 11635 Athens, Greece.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Simandiras
authors.affiliation: Faculty of Chemistry, National and Kapodistrian University of Athens , 15771 Athens, Greece.
authors.forename: Spyros
authors.initials: S
authors.lastname: Koinis