Which among the following compounds give yellow solid when reacted with NaOI/NaOH? Choose the correct answer from the options given below :
- (A) and (C) Only
- (C) and (D) Only
- (B), (C) and (E) Only
- (A), (C) and (D) Only
Answer
(1) (A) and (C) Only
Solution
Yellow solid = iodoform, CHI3 (iodoform test).
It is given by compounds having CH3CO- (attached to C or H) or CH3CH(OH)- (oxidised to CH3CO- by NaOI).
(A) Butan-2-ol has CH3CH(OH)- positive.
(B) Propan-1-ol has no CH3CH(OH)- negative.
(C) Butan-2-one is a methyl ketone positive:
CH3COC2H5 + 3NaOI CI3COC2H5 + 3NaOH
CI3COC2H5 + NaOH CHI3 + C2H5COONa
(D) In acetic acid, C=O is part of –COOH (resonance-stabilised, α-H not activated) negative.
(E) Propanal, CH3CH2CHO, has no CH3CO- negative.
(A) and (C) only.
Answer: (1)