Mesitylene tricarbonyl tungsten

Later on, it was demonstrated that these heterocycles can undergo Diels-Alder reactions in the presence of an electrophile (Ss or Mel) and dienophiles <2002T1573, 2003HAC560>. These phosphoms-containing heterocycles were found to produce, upon reaction with tricarbonyl(cycloheptatriene)molybdenum(0) or tricarbonyl(mesitylene) tungsten(O), cr-complexes of the type L2M(CO)4 or I,(M(CO)( instead of 7t-complexes <1998EJI1079>. Some derivatives of this heterocycle were also found to display remarkable antibacterial activity <2005BML937>. 

There are several classic examples of the use of FTIR spectroelectrochemistry in elucidating the EC reactions of oxidized carbonyl complexes. These include the isomerization of 17e complexes for example, the isomerization of m-[Mo(CO)2(P-P)2]+ to the trans-isomer.139 Similarly, the cis-isomer of [Re(CO)2(P P)2]+ or [Re(CO)(P—P)2X] will isomerize on oxidation as monitored in a reflection IR cell.140 One-electron oxidation of [IrH(CO)(PPh3)3] is reversible, but further oxidation to the dication induces hydride oxidation and the appearance of bands due to the 16e complex [Ir(CO)(PPh3)3]+.141 Oxidation of arene tricarbonyls of Group 6 metals is frequently irreversible, especially in coordinating solvents at ambient temperature. However, the mesitylene tungsten tricarbonyl complex is oxidized by two electrons with the reversible take up of MeCN.142... 

Figure 3-29 Experimental and simulated CVs of the oxidation of 1 mM tricarbonyl-(mesitylene)-tungsten (W) in acetonitrile at 298 K. (Adapted from Reference 14.)...

An overview of the effect of catalyst in the reaction of arenes with chromium hexacarbrmyl has been published. The reactivity of 17-, 18-, and 19-etectron catkMis generated electrochemically from mesitylene-tungsten tricarbonyl has been examined. The gas phase ion chemistry of a range of arene tricarbonylchromium complexes has been investigated by F.T. mass spectrometry. An improved synthesis of substituted naphthalene chromium carbonyls has appeared. ... 

Tricarbonyl(6,6-diphenylfulvene)chromium(0) (52) was obtained by reaction of 6,6-diphenylfulvene with hexacarbonylchromium in 64% yield [56]. Later it was shown that almost quantitative yields can be obtained under photochemical reaction conditions starting from (benzene)Cr(CO)3 or from (mesitylene)Cr(CO)3 as the complexation reagent [63]. The corresponding molybdenum and tungsten complexes were prepared by treatment of the ligands with tris(acetonitrile)M(CO)3 (M = Mo, W) [64]. Olefin complex 53 was obtained by Wilkinson and Altman in 51% yield from 6,6-diphenylfulvene and bis(dicarbonylchlororhodium). Similar complexes were prepared with other rhodium reagents [58]. Hiibel and Weiss [59] prepared the diene tri-carbonyliron complex 54 (11-30%) in addition to the dinuclear complex, in which either one of the endocyclic double bonds is coordinated at Fe(CO)4 (49-66%). 

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