Methylierung eines schwefelreichen dimolybdänkomplexes: darstellung, trennung und charakterisierung von (C5Me5)2Mo2(μ-SCH3)2(μ-S)2 in zwei isomeren formen

Abstract

The methylation reaction of (C,Me,)2M%( &3z)(~-S)2 (Ia) leads to two isomers of composition (C,Me,),Mo,(SMe),S, (IVa and IVb) which were separated by column chromatography. As an intermediate product of this reaction the iodinecontaining adduct (C,Me,),Mo$,I, is formed. All compounds were investigated by means of 'H and 95Mo NMR spectroscopy a s well as by an X-ray structure analysis in the case of IVa. Thus, the SCH, ligands in IV are found to be arranged in a tram position. As a further result a cleavage of the $-disulfur bridge, originally present in Ia, has been found to occur in the second step of the reaction sequence.

Transition-Metal-Substituted Dichlorobismuthanes as Starting Materials for Novel Bismuth−Transition-Metal Clusters

“…Mo−Cl distances in 7 (2.3942(14)−2.496(2) Å) are similar to those in the cation [(Cp*MoCl) 2 (μ-Cl) 3 ] + (2.422−2.460 Å) and are in the usual range for bridging chlorine atoms. The Mo−Mo contact of 2.7717(8) Å is in the upper range of Mo(III)−Mo(III) bonds (from 2.573 Å in [(MoCp Me )(μ-S)(μ-SCH 3 )] 2 to 2.743 Å in [(MoCl 3 ) 2 (μ-Cl) 3 ] 3- ) but can be regarded as bonding, which is proven by the diamagnetism of compound 8 .…”

Synthesis and Structural Characterization of Tetranuclear, Bimetallic Sulfido Nitrosyl and Carbonyl Clusters of the Type Cp2M2M‘2S3,4Ln (M = Mo, W; M‘ = Fe, Co; L = NO, CO)

“…The clusters Cp # 2 Mo 2 Fe 2 S 4 (NO) 2 (Cp # = Cp Et , Cp) were synthesized using different Mo/S cluster synthons and two Fe−nitrosyl complexes as the source of the FeNO vertex, all of which resulted in a product with the same cluster core. In the first case, the product of the reaction of Cp Et 2 Mo 2 S 4 with 1 equiv of I 2 , to which the formula [Cp Et 2 Mo 2 S 4 ] 2+ I - 2 has been ascribed by Brunner and co-workers, was prepared. On the basis of this molecular formula, 2 equiv of Na[Fe(CO) 3 NO] in THF was added and the reaction was allowed to proceed at room temperature for 30 min (Scheme ).…”

“…Reagent grade solvents were dried and distilled prior to use: toluene from Na/benzophenone, decahydronaphthalene (decalin), dichloromethane, and hexane from CaH 2 , and acetonitrile (predried over 3 Å sieves) from B 2 O 3 . Cp 2 Mo 2 (S) 2 (μ-SH) 2 /Cp‘ 2 Mo 2 (S) 2 (μ-SH) 2 , Cp Et 2 Mo 2 S 4 , Cp* 2 W 2 S 4 /Cp Et 2 W 2 S 4 , Cp* 2 W 2 S 3 (CO) 2 /Cp Et 2 W 2 S 3 (CO) 2 , Cp Et 2 Mo 2 S 4 I 2 (Cp = C 5 H 5 , Cp‘ = C 5 H 4 Me, Cp* = C 5 Me 5 , and Cp Et = C 5 Me 4 Et), Na[Fe(CO) 3 (NO)], Fe(NO) 2 (CO) 2 , and Co(CO) 3 (NO) were prepared according to published procedures or slight adaptations thereof. (Note: In all the following procedures that use Cp # 2 M 2 S 4 , the “as prepared” mixture of isomers was used.…”