Which of the following is/are wrong:
Primary amines form isocyanide with CHCl3 + KOH not amides.
CCl4 directly attacks on the ring. No carbene formation
Not carbene but nitrene is the attacking species
Let's evaluate each statement step by step:
Phenol with CCl4 and NaOH undergoes Reimer-Tiemann reaction producing salicylaldehyde, not salicylic acid. The intermediate is dichlorocarbene (:CCl2), not carbene (:CH2).
Reaction:
Conclusion: This statement is incorrect
Esters react with Grignard reagents to produce tertiary alcohols. Ethyl methanoate (HCOOC2H5) with excess CH3MgBr gives:
First addition: HCOOC2H5 + CH3MgBr → HC(OH)(CH3)OC2H5
Second addition: HC(OH)(CH3)OC2H5 + CH3MgBr → (CH3)2C(OMgBr)OC2H5
Hydrolysis gives 2-methylpropan-2-ol, a tertiary alcohol.
Conclusion: This statement is correct
:CH2 (methylene carbene) vs (methyl radical)
Carbenes are highly reactive due to electron deficiency. Radicals like methyl radical are more stable due to delocalization and lower energy state.
Conclusion: The statement that :CH2 is more stable is incorrect
Amides with CHCl3 and KOH undergo Hofmann degradation/isocyanide test. Acetamide (CH3CONH2) produces methyl isocyanide (CH3NC), which has an extremely foul odor.
Reaction:
Conclusion: This statement is correct
Statements 1 and 3 are wrong.
Reimer-Tiemann: Phenol + CHCl3 + NaOH → Salicylaldehyde
Ester + 2RMgX → Tertiary alcohol after hydrolysis
Hofmann isocyanide test: RCONH2 + CHCl3 + 3KOH → RNC + 3KCl + 3H2O
Sodium phenoxide when heated with CO2 under pressure at 125°C yields a product which on acetylation produces C.
The major product C would be:
The major product in the following reaction is
