Problems and exercisesAsymmetric organocatalysis: List and MacMillan
Exercise 1
Why does iminium organocatalysis need a secondary amine and an acid co-catalyst? Why is a conjugated iminium ion a better dienophile than the unsaturated aldehyde from which it comes?
Exercise 2
Which product is obtained in the Michael addition of butanal to (E)-β-nitrostyrene catalysed by the trimethylsilyl ether of (S)-diphenylprolinol? How would you convert it into a 3,4-disubstituted pyrrolidine?