In the reaction

the structure of the product T is :

Solution

In the following reaction sequence, the correct structures of E, F and G are

[* implies ¹³C labelled carbon]

Solution

In Cannizzaro reaction given below

the slowest step is :

the transfer of hydride to the carbonyl group
the abstraction of proton from the carboxylic group
the deprotonation of Ph CH₂OH
the attack of : $\overset{ \bigoplus }{OH}$ at the carboxyl group

Solution

An organic compound ‘A’ on treatment with NH₃ gives ‘B’which on heating gives ‘C’, ‘C’ when treated with Br₂ in the presence of KOH produces ethylamine. Compound ‘A’ is:

CH₃COOH
CH₃CH₂ CH₂ COOH
CH₃CH₂COOH

Solution

Since, C when heated with Br₂ in presence of KOH produces ethylamine, hence it must be propanamide and hence the organic compound (A) will be propanoic acid. The reactions follows.

The order of reactivity of phenyl magnesium bromide(PhMgBr) with the following compounds

III > II > I
II > I > III
I > III > II
I > II > III

Solution

The reactivity of the carbonyl group toward the nucleophilic addition reactions depend upon themagnitude of the positive charge on the carbonyl carbon atom (electronic factor) and also on the crowding around the carbonyl carbon atom in the transition state (steric factor). Both these factors predict the following order

(due to steric crowding).

Which one of the following compounds will be most readily dehydrated?

Solution

The intermediate is carbocation which is destabilised by C = O group in the first three cases. In(d),α–hydrogen is more acidic which can be removed as water. Moreover, the positive charge on the intermediate carbocation is relatively away from the C = O group.

In a set of reactions, ethylbenzene yield a product D.

Identify D:

Solution

Which of the following reagent(s) used for the conversion?

glycol/LiAlH₄/H₃O⁺
glycol/NaH/H₃O⁺
LiA1H₄
NaBH₄

Solution

Cannizaro’s reaction is not given by :

CH₃CHO
HCHO

Solution

Only those aldehydes which do not have α-H atom undergo Cannizaro’s reaction. Hence CH₃CHO will not undergo Cannizaro’s reaction as it has 3 α-H atoms.

Calculate number of molecules of Grignard reagent consumed by 1 molecule of following compound.

Solution

UnAttempted

10

Attempted

0

Correct

0

Wrong

0

Complete