The second complex is ru2 d 8 16 e which has an empty

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The second complex is Ru(2+) d816 e, which has an empty orbital. This will be the one more likely to do an oxidative addition with H2.e) Pt(CH2=CH2)3– or –Cr(CO)3(PMe3)3with HSiMeHSiMe3is an non-electrophillic substrate and needs an empty orbital to coordinate to the metal prior to doing an oxidative addition of the H-Si bond. The first Pt complex is Pt(0) d1016 ewith alkene ligands that are only weakly to moderately coordinated. The Cr complex is in the 0 oxdiation state, d618 e, which has strongly coordinated donating phosphines and -backbonding CO ligands. Indeed, this (or similar) Pt complex forms one of the most active catalysts known for the hydrosilylation of alkenes.
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3) Drawing Organometallic Reactions Consider the following reactions. Sketch out the final product clearly showing the structure and geometry. The reaction steps listed may not be in the correct order. Include a brief and clear explanation of the correct order of steps and why they go in that order. a) [Fe(CO)4]2–+ CH3Br (oxidative addition) b) [Ru(PMe3)(CO)4(acyl)]+(elimination, ligand dissociation) RuCCCPMe3CCOCH3OOOO-CORuCCPMe3CCOCH3OOORuCCPMe3CCOOOOCH318e-16e-18e-Ligand dissociation has to be the first step in order to make an empty orbitial cisoidal to the acyl group for the carbonyl elimination. c) Ir(CH3)2Cl(dmpe) + N≡CCH3(reductive elimination, ligand addition) IrClH3CMe2PPMe2CH3Ir(+3), 16e-IrClMe2PPMe2-CH3CH3Ir(+1), 14e-IrClMe2PPMe2Ir(+1), 16e-NCMeNMeCReductive elimination is OK as a first step due to the unsaturation of the Ir(+3) complexd) CpMo(H)(CH2=CHCH3)(dmpe) + 2CO (2 migratory insertions, 2 ligand additions) MoPR2HR2PMoPR2R2P+COMoPR2R2PCOMoPR2R2PPrOmigratoryinsertion1. migratoryinser tion2. +COCO
4) OMITTED BUT THE QUESTIONS NOT RE-ORDERED CFeCCCH3COOOOBrFe(0)d818e-CFeCCCOOOO2-BrCHHHFe(2-)d1018e-Charge balance!! If you start with a dianionic complex the negative charges can’t simply go away!! The Fe(2-) center is oxidized by two electrons to make an Fe(0) center with an anionic CH3ligand (overall negative charge). The other negative charge goes to the bromide anion that does not coordinate to the 18e- [Fe(CH3)(CO)4]- complex. Many of you put down Fe(CH3)(Br)(CO)4as your answer. This is an Fe(2+) complex which represents a 4e- oxidation of the metal center and loss of the dianionic charge. Also, the question does not state that a ligand dissociation or substitution occurs. So the transformation should not be assumed to continue to Fe(CO)3(CH3)(Br)
5) Describing Organometallic Reactions

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