Question

a. Alkenes with electron withdrawing groups are good dienophiles-True/False b. Wolfkishner reaction is helpful to convert an ester to alkane. True false c. Tertiary alcohol will be formed by the reaction between a ketone and Grignard reagent True/ false d. A cyclic conjugated compound with 6 pi electron is aromatic- True/ False e. Addition of CO; to Methyl magnesium bromide is a nucleophilic addition Truel false f A good protecting group should be cleaved during the progress of the reaction-True False g 1,4-addition product is the thermodynamic product in the addition of conjugated diene- Truel false h. Ir spectrum can be used to follow the Wittig reaction -True/ False i. Benzene is UV active True False j Primary carbocation is more stable than secondary carbocation- True/ False

Answer 1

1. True -Dienophile are electron deficient species, they are diene loving,
2. False –it converts aldehyde ketone to alkane
3. True. – Grignard reagent is used to introdude alkyl/aryl group. Aldehyde give secondry alcohol and tertiary is formed by ketone
4. True- it follows 4n+2 elctron rule
5. True- due to presence of multiple bonds
6. False- A protecting group is used to protect some part of molecule I course of reaction so it should not cleaved
7. True-Temperature is used in 1, 4 to control 1,4 formation over 1,2
8. True- WITTIG converts aldehyde ketone to alkene. The alkene peaks can be easily identified by IR
9. True – Due to conjugation
10. False- Secondrty is more stable due to two electron donating alkyl groups as compare to 1 primary