Draw the structures of organic compounds A and B. Omit all byproducts.

Solution :-

For the given reaction steps alkene is reacted with the B2H6/THF and H2O2,NaOH, H2O in the first step which converts the alkene in to the ethanol.

Then ethanol is reacted with the PCC (pyridinium chloro chromate) which is oxidizing agent. Therefore it converts the alcohol into the aldehyde.

Then in the final step aldehyde was reacted with the Grignard reagent to add the ethyl group to the aldehyde and produce alcohol and again the alcohol is reacted with CrO3 which oxidizes the secondary alcohol to ketone product.

Following image shows the structures of the products ‘A’ and ‘B’

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