- 4 Hydrocyanation Involves The Addition Of Hcn To An Alkene To Form A New C C Bond And Introduce New Functionality Into 1 (163.05 KiB) Viewed 10 times
level diagram to describe the interactions between the nickel and
the alkene ligand. You must include sketches of the orbital
overlaps for full marks. [4 marks] ii. Suggest a strategy to
increase the strength of the interaction between the metal and
alkene ligand. Briefly explain how and why this strategy affects
metal-carbon and carbon-carbon bond strength and geometry
4. Hydrocyanation involves the addition of HCN to an alkene to form a new C-C bond and introduce new functionality into the compound. A proposed mechanism for the hydrocyanation of ethene to form propionitrile is shown below. 1 RP.Ni Et CN HCN R₃pm A E R3P... 2 5 RP Ni-PR3 R₃pm NITH CN Et CN B D PR3 PR3 R3P RP, Ni. Ni-H Et CN 4 C CN 3 a. Draw an overall reaction scheme for this catalytic process. [2 marks] b. Provide the number of valence electrons, coordination number, oxidation state and dn-configuration for complexes 1-5. Hint: assume CN is an X- type ligand [5 marks] c. Name steps A - E. [5 marks] d. Consider complex 1. i. Draw a molecular orbital (MO) energy level diagram to describe the interactions between the nickel and the alkene ligand. You must include sketches of the orbital overlaps for full marks. [4 marks] ii. Suggest a strategy to increase the strength of the interaction between the metal and alkene ligand. Briefly explain how and why this strategy affects metal-carbon and carbon-carbon bond strength and geometry. [4 marks]