Question

QUESTION 1 15 marks] e structures (no mechanism required) of the TWO (2) stereoisomeric oxiranes formed from the epoxidation reaction of (E)-2-butene with meta-chloroperoxybenzoic acid l mark] (i) Assign R or S stereochemistry to the stereogenic carbons in each of the oxirane products. I1 mark] chch yfat muf l mark] (iv) Indicate and explain the expected stereochemistry in the product(s) of the reaction below. In your answer you must make reference to the key intermediate involved in the mechanism. HO Br Br2 H20 /THF 2 marks

For ii I got rs and Sr stereochemistry. For iii I got racemate. For Iv, I think there's 4 stereo isomers? I'm not sure.

Answer 1

CH3 E-2-onee R' R Aand @ howe and have no plane of we They are enanticmers r duue cemire BY 0 Сусі, - 언 B H brom omiliw R' 0 D and in 3D Space ar) S o TD Stere osomers dbtain