Lecture 2

Question 1

What catalysts are used in alkene metathesis?

Answer 1

Grubbs or Schrock

• Ru catalysts more stable but less reactive
• Mo often requires a glove box

Question 2

What are the challenges of alkene metathesis?

Answer 2

• Mixture of cis and trans products
• some steps being reversible

Develop a more complex catalyst to allow selectivity

Question 3

What is one requirement for alkyne metathesis and why?

Answer 3

• Alkynes need terminal Me groups

- Prevent insertion into a carbon hydrogen bond to form a vinyl species

Question 4

How do you achieve specific alkene orientation in enyne metathesis?

Answer 4

• react alkynes and then selectively reduce the products