An alkene ‘A’ (Mol. formula C 5 H 10 ) on ozonolysis gives a mixture of two compounds ‘B’ and ‘C’. Compound ‘B’ gives positive Fehling’s test and also forms iodoform on treatment with I 2 and NaOH. Compound ‘C’ does not give Fehling’s test but forms iodoform. Identify the compounds A, B and C. Write the reaction for ozonolysis and formation of iodoform from B and C.
Answer
A is an Alkene with the chemical formula: C 5 H 10
Its structure can be drawn as any of the following:
Compound A is an alkene, so, on ozonolysis it will give carbonyl compounds B and C.
We know that,
- B gives positive Fehling’s test : so it is an aldehyde .
It gives positive Iodoform tes t so it has CH3C=O group . This means the aldehyde is acetaldehyde .
Also,
- C does not give Fehling’s test : it is a ketone .
- It gives positive iodoform test so it is a methyl ketone.
- A methyl ketone must have at least three carbon atoms .
Based on ozonolysis mechanism,
Only A= satisfies this condition.