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Study Guide for Test 4 in CHEM 411


  1. Define:

    1. elementary or fundamental step

    2. rate-determining step

    3. inner-sphere electron transfer

    4. outer-sphere electron transfer

    5. insertion reaction

    6. beta-hydride elimination

    7. oxidative addition

    8. reductive elimination

    9. coordinative unsaturation

    10. electronic unsaturation

    11. chain-walking

    12. hydrogenation of an alkene

    13. hydroformylation of an alkene

    14. associative mechanism

    15. dissociative mechanism

    16. trans effect in square planar complexes

  2. Given the data below, determine the correct rate law, and give a reasonable speculation as to the type of mechanism that might lead to this type of kinetic rate law.

    Ni(CO)4 + PPh3 ------------------> Ni(CO)3(PPh3) + CO

    Experiment
    [Ni(CO)4], M
    [PPh3], M
    Rate, s-1
    i
    0.100
    0.100
    1.2 x 10-3
    ii
    0.200
    0.100
    2.4 x 10-3
    iii
    0.300
    0.100
    3.6 x 10-3
    iv
    0.100
    0.200
    1.2 x 10-3
    v
    0.100
    0.300
    1.2 x 10-3


  3. Given the data below, determine the correct rate law, and give a reasonable speculation as to the type of mechanism that might lead to this type of kinetic rate law.

    Cr(CO)6 + PPh3 ------------------> Cr(CO)5(PPh3) + CO

    Experiment
    [Cr(CO)6], M
    [PPh3], M
    Rate, s-1
    i
    0.100
    0.100
    1.02 x 10-4
    ii
    0.200
    0.100
    2.04 x 10-4
    iii
    0.300
    0.100
    3.06 x 10-
    iv
    0.100
    0.200
    2.04 x 10-4
    v
    0.100
    0.300
    3.06 x 10-4


  4. Write the mechanism of hydrogenation of 1-butene by Rh(PPh3)3Cl. For each step determine the oxidation state of the metal and the numberr of electrons around the metal and indicate both.

  5. Demonstrate how (C5H5)2Zr(H)Cl can act as an isomerization catalyst for cis-3-hexene to be converted into 1-hexene by drawing the mechanism for such a process. What is driving this process? For each step determine the oxidation state of the metal and the numberr of electrons around the metal and indicate both.

  6. Write a mechanism for hydroformulation of 3,3-dimethyl-1-butene using Rh(PPh3)3Cl. For each step determine the oxidation state of the metal and the numberr of electrons around the metal and indicate both.

  7. Write the mechanism for the Wacker process. (Production of acetaldeyde from ethylene and dioxygen mediated by PdCl42-.) How is the catalytic cycle acheived in this process?

  8. Using Al(CH3)3 and Cl4W=O to produce the catalyst, write a mechanism for the alkene (olefin) metathesis of styrene (phenylethlene). You need show only the productive pathways.

  9. Write the mechanism for the hydrogenation of 1-hexene by (C5H5)2ZrH2. For each step determine the oxidation state of the metal and the numberr of electrons around the metal and indicate both.

  10. Explain the difference between isotactic, syndiotactic, and atactic polymers produced from 1-alknenes. For simplicities sake, draw structures of polypropylene.

  11. Write the Cossee-Cossee mechanism for the polymerization of ethylene using Al(CH2CH3)3 and TiCl4.

  12. Explain the advantages of a single site catalyst over a traditional Ziegler-Natta catalysts. What are the disadvantages?

  13. For the reactions below, use the trans effect to predict the products. The series for trans directors is H2O < OH- < F- ~ RNH2 ~ py ~ NH3 < Cl- < Br- < SCN- ~ I- ~ NO2- ~ C6H5- < SC(NH2)3 ~ CH3- < NO ~ H- ~ PR3 < C2H4 ~ CN- ~ CO .