Draw structures of the following derivatives. (i) The 2,4-dinitrophenylhydrazone of benzaldehyde (ii) Cyclopropanone oxime (iii) Acetaldehydedimethylacetal (iv) The semicarbazone of cyclobutanone (v) The ethylene ketal of hexan-3-one (vi) The methyl hemiacetal of formaldehyde
Ph-CH=N-NH-C₆H₃(NO₂)₂ (2,4-dinitrophenylhydrazone of benzaldehyde): Benzene ring attached to -CH=N-NH- group, which is further attached to a phenyl ring having -NO₂ groups at positions 2 and 4.
Cyclopropanone oxime: A three-membered cyclopropane ring with C=N-OH replacing the carbonyl group.
Acetaldehydedimethylacetal: CH₃-CH(OCH₃)₂ — two methoxy groups attached to the same carbon in place of the carbonyl oxygen.
Semicarbazone of cyclobutanone: A four-membered cyclobutane ring with C=N-NH-CONH₂ replacing the carbonyl group.
Ethylene ketal of hexan-3-one: CH₃CH₂-C(OCH₂CH₂O)-CH₂CH₂CH₃ — ethylene glycol ketal formed at the carbonyl position.
Methyl hemiacetal of formaldehyde: H-CH(OH)(OCH₃) — one hydroxyl and one methoxy group attached to the same carbon.
Explanation
These derivatives are formed by nucleophilic addition reactions at the carbonyl carbon. The 2,4-DNP derivative, oxime, and semicarbazone involve condensation with -NH₂ containing reagents, eliminating water. Acetals and ketals form from alcohols with aldehydes and ketones respectively. Hemiacetals are intermediates with one -OH and one -OR group.