An alkene ‘A’ (Mol. formula C5H10) 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 I2 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.


The compounds A, B , C are

,


2 Methyl but-2-ene, Acetaldehyde and acetone respectively.


Among B and C former is an aldehyde(responds to Felling’s test) and latter is obviously a ketone as both forms iodoforms on treatment with I2 and NaOH. And from this clue, we can identify the alkene ‘A’ (Mol. formula C5H10) which is 2 Methyl but-2-ene also as ozonolysis does not disrupt the symmetry of the molecule.


The equation for ozonolysis of alkene
A :



‘A’ ‘ C’ ‘B’


Now, for compound ‘B’ (acetaldehyde) the iodoform reaction is as follows :



It also gives Felling’s test which is the way to identify it as an aldehyde :



Compound ‘C’ which is a ketone (acetone) the iodoform reaction is as follows:



But it is unable to give Fehling’s test.


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