General Mechanisms

Question 1

Inductive effect

Answer 1

Neighbouring atoms can push/pull electrons in sigma bonds creating dipole in C-X bond

Question 2

What effects inductive effect

Answer 2

Electronegative and bond length

Question 3

Mesomeric effect

Answer 3

Donation/withdrawal of electron density via pi-bonds causing polarisation of C-X bond

Question 4

Sn2

Answer 4

Nucleophile attacks less substituted carbon

Question 5

Describe configuration in Sn2 reactions

Answer 5

Inversion of configuration

Question 6

Sn2 for cyclohexanes when the leaving group is

Answer 6

Axial as there’s less steric hinderance of approaching nucleophile

Question 7

How is configuration retained in nucleophilic substitutions

Answer 7

2Sn2 or Sni

Question 8

Sni

Answer 8

Substitution nucleophilic intramolecular

Question 9

Angle of attack of nucleophile in Sn

Answer 9

<90 to leaving group

Question 10

What do addition reactions at carbonyls form

Answer 10

Racemate as the nucleophile can approach from the re or si fac

Question 11

Lowest every conformation for having S, M and L groups around a carbon atom bonded to a C=O

Answer 11

L perpendicular to plane of carbonyl group

Question 12

Lowest energy approach of nucleophile

Answer 12

Least sterically hindered

Question 13

Antimarkovnikov

Answer 13

Nucleophile attacks least substituted carbon

Question 14

Why are epoxides reactive

Answer 14

Ring strain of three membered ring