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Page 1 ? Points to remember in Aldehyde & ketone Aldol condensation : Carbonyl compounds having acidic sp 3 ?-H shows this reaction in presence of dil. NaOH or dil. acid. O C CH 2 | H 3 ? ? Dil NaOH ???? H | CHO CH C CH | OH 2 3 ? ? ? O H , H 2 ? ? ? ? ? ? ? ? CHCHO CH CH 3 ? Crossed aldol condensation (i) CH 3 CHO + HCHO ? ? ? ? ? ? ? NaOH . Dil HOCH 2 ?CH 2 ?CHO ? ? ? ? ? ? ? ? O H / H 2 CH 2 =CH?CHO (ii) CH 3 COCH 3 + HCHO ? ? ? ? ? ? ? NaOH . Dil CH 3 CO?CH 2 CH 2 OH ? ? ? ? ? ? ? ? O H / H 2 CH 3 CO?CH=CH 2 Cannizzaro reaction : Carbonyl compounds not having sp 3 ?-H shows following disproportion reaction %) 50 ( NaOH H C H 2 || O ? ? ? ?? ? OH CH 3 ? + HCOONa CHO H C 2 5 6 + %) 50 ( NaOH ?? ? OH CH H C 2 5 6 + benzoate . Sol COONa H C 5 6 Crossed Cannizzaro reaction : + HCHO + %) 50 ( NaOH ?? ? + formate . Sod HCOONa Formation of hydrzones and azines C=O + NH NH 2 2 C NHNH 2 OH ?H O 2 C= NNH 2 CO C= N?N = C Perkin reaction : When benzaldehyde (or any other aromatic aldehyde) is heated with the Page 2 ? Points to remember in Aldehyde & ketone Aldol condensation : Carbonyl compounds having acidic sp 3 ?-H shows this reaction in presence of dil. NaOH or dil. acid. O C CH 2 | H 3 ? ? Dil NaOH ???? H | CHO CH C CH | OH 2 3 ? ? ? O H , H 2 ? ? ? ? ? ? ? ? CHCHO CH CH 3 ? Crossed aldol condensation (i) CH 3 CHO + HCHO ? ? ? ? ? ? ? NaOH . Dil HOCH 2 ?CH 2 ?CHO ? ? ? ? ? ? ? ? O H / H 2 CH 2 =CH?CHO (ii) CH 3 COCH 3 + HCHO ? ? ? ? ? ? ? NaOH . Dil CH 3 CO?CH 2 CH 2 OH ? ? ? ? ? ? ? ? O H / H 2 CH 3 CO?CH=CH 2 Cannizzaro reaction : Carbonyl compounds not having sp 3 ?-H shows following disproportion reaction %) 50 ( NaOH H C H 2 || O ? ? ? ?? ? OH CH 3 ? + HCOONa CHO H C 2 5 6 + %) 50 ( NaOH ?? ? OH CH H C 2 5 6 + benzoate . Sol COONa H C 5 6 Crossed Cannizzaro reaction : + HCHO + %) 50 ( NaOH ?? ? + formate . Sod HCOONa Formation of hydrzones and azines C=O + NH NH 2 2 C NHNH 2 OH ?H O 2 C= NNH 2 CO C= N?N = C Perkin reaction : When benzaldehyde (or any other aromatic aldehyde) is heated with the anhydride of an aliphatic acid (containing two ?-hydrogen atoms) in the presence of its sodium salt, condensation takes place to form a ?-arylacrylic acid ; e.g., with acetic anhydride and sodium acetate, cinnamic acid is formed. C 6 H 5 CHO + (CH 3 CO) 2 O ? ? ? ? ? ? Na CO CH 2 3 C 6 H 5 CH = CHCO 2 H Mechanism : CH 3 COOCOCH 3 + CH 3 CO 2 ? H CO CH COOCOCH H C 2 3 3 2 ? ? C H C + CH COOCOCH 6 5 2 3 O H C H CCH COOCOCH 6 5 2 3 O H H + C H CCH COOCOCH 6 5 2 3 OH H ? ? ? ? ? O H ? 2 C 6 H 5 CH=CHCOOCOCH 3 ? ? ? ? O H 2 C 6 H 5 CH = CHCO 2 H + CH 3 CO 2 H Haloform reaction : Acetaldehyde and methylalkyl ketones react rapidly with halogen (Cl 2 , Br 2 or I 2 ) in the presence of alkali to give haloform and acid salt. 3 CH C R || O ? ? ? ? ? ? ? ? ? NaOH / Br 2 3 CHBr ONa C R || O ? ? ? (Bromoform) In this reaction ? CH 3 of ? ? C CH || O 3 group is converted into haloform as it contains acidic hydrogen atom and rest-part of alkyl methyl ketone give acid salt having carbon atom corresponding to alkyl ketone. Preparation of haloform from methylketone involves two steps. (a) Halogenation 3 CH C R || O ? ? ? ? ? ? 2 Br 3 CBr C R || O ? ? (Halogenation) Page 3 ? Points to remember in Aldehyde & ketone Aldol condensation : Carbonyl compounds having acidic sp 3 ?-H shows this reaction in presence of dil. NaOH or dil. acid. O C CH 2 | H 3 ? ? Dil NaOH ???? H | CHO CH C CH | OH 2 3 ? ? ? O H , H 2 ? ? ? ? ? ? ? ? CHCHO CH CH 3 ? Crossed aldol condensation (i) CH 3 CHO + HCHO ? ? ? ? ? ? ? NaOH . Dil HOCH 2 ?CH 2 ?CHO ? ? ? ? ? ? ? ? O H / H 2 CH 2 =CH?CHO (ii) CH 3 COCH 3 + HCHO ? ? ? ? ? ? ? NaOH . Dil CH 3 CO?CH 2 CH 2 OH ? ? ? ? ? ? ? ? O H / H 2 CH 3 CO?CH=CH 2 Cannizzaro reaction : Carbonyl compounds not having sp 3 ?-H shows following disproportion reaction %) 50 ( NaOH H C H 2 || O ? ? ? ?? ? OH CH 3 ? + HCOONa CHO H C 2 5 6 + %) 50 ( NaOH ?? ? OH CH H C 2 5 6 + benzoate . Sol COONa H C 5 6 Crossed Cannizzaro reaction : + HCHO + %) 50 ( NaOH ?? ? + formate . Sod HCOONa Formation of hydrzones and azines C=O + NH NH 2 2 C NHNH 2 OH ?H O 2 C= NNH 2 CO C= N?N = C Perkin reaction : When benzaldehyde (or any other aromatic aldehyde) is heated with the anhydride of an aliphatic acid (containing two ?-hydrogen atoms) in the presence of its sodium salt, condensation takes place to form a ?-arylacrylic acid ; e.g., with acetic anhydride and sodium acetate, cinnamic acid is formed. C 6 H 5 CHO + (CH 3 CO) 2 O ? ? ? ? ? ? Na CO CH 2 3 C 6 H 5 CH = CHCO 2 H Mechanism : CH 3 COOCOCH 3 + CH 3 CO 2 ? H CO CH COOCOCH H C 2 3 3 2 ? ? C H C + CH COOCOCH 6 5 2 3 O H C H CCH COOCOCH 6 5 2 3 O H H + C H CCH COOCOCH 6 5 2 3 OH H ? ? ? ? ? O H ? 2 C 6 H 5 CH=CHCOOCOCH 3 ? ? ? ? O H 2 C 6 H 5 CH = CHCO 2 H + CH 3 CO 2 H Haloform reaction : Acetaldehyde and methylalkyl ketones react rapidly with halogen (Cl 2 , Br 2 or I 2 ) in the presence of alkali to give haloform and acid salt. 3 CH C R || O ? ? ? ? ? ? ? ? ? NaOH / Br 2 3 CHBr ONa C R || O ? ? ? (Bromoform) In this reaction ? CH 3 of ? ? C CH || O 3 group is converted into haloform as it contains acidic hydrogen atom and rest-part of alkyl methyl ketone give acid salt having carbon atom corresponding to alkyl ketone. Preparation of haloform from methylketone involves two steps. (a) Halogenation 3 CH C R || O ? ? ? ? ? ? 2 Br 3 CBr C R || O ? ? (Halogenation) (b) Alkalihydrolysis 3 CBr C R || O ? ? ? ? ? ? ? NaOH CHBr 3 + ONa C R || O ? ? (Alkalihydrolysis) Note : This reaction is used to distinguish the presence of ? ? C CH || O 3 group. Other reactions : (1) (2) (3) Page 4 ? Points to remember in Aldehyde & ketone Aldol condensation : Carbonyl compounds having acidic sp 3 ?-H shows this reaction in presence of dil. NaOH or dil. acid. O C CH 2 | H 3 ? ? Dil NaOH ???? H | CHO CH C CH | OH 2 3 ? ? ? O H , H 2 ? ? ? ? ? ? ? ? CHCHO CH CH 3 ? Crossed aldol condensation (i) CH 3 CHO + HCHO ? ? ? ? ? ? ? NaOH . Dil HOCH 2 ?CH 2 ?CHO ? ? ? ? ? ? ? ? O H / H 2 CH 2 =CH?CHO (ii) CH 3 COCH 3 + HCHO ? ? ? ? ? ? ? NaOH . Dil CH 3 CO?CH 2 CH 2 OH ? ? ? ? ? ? ? ? O H / H 2 CH 3 CO?CH=CH 2 Cannizzaro reaction : Carbonyl compounds not having sp 3 ?-H shows following disproportion reaction %) 50 ( NaOH H C H 2 || O ? ? ? ?? ? OH CH 3 ? + HCOONa CHO H C 2 5 6 + %) 50 ( NaOH ?? ? OH CH H C 2 5 6 + benzoate . Sol COONa H C 5 6 Crossed Cannizzaro reaction : + HCHO + %) 50 ( NaOH ?? ? + formate . Sod HCOONa Formation of hydrzones and azines C=O + NH NH 2 2 C NHNH 2 OH ?H O 2 C= NNH 2 CO C= N?N = C Perkin reaction : When benzaldehyde (or any other aromatic aldehyde) is heated with the anhydride of an aliphatic acid (containing two ?-hydrogen atoms) in the presence of its sodium salt, condensation takes place to form a ?-arylacrylic acid ; e.g., with acetic anhydride and sodium acetate, cinnamic acid is formed. C 6 H 5 CHO + (CH 3 CO) 2 O ? ? ? ? ? ? Na CO CH 2 3 C 6 H 5 CH = CHCO 2 H Mechanism : CH 3 COOCOCH 3 + CH 3 CO 2 ? H CO CH COOCOCH H C 2 3 3 2 ? ? C H C + CH COOCOCH 6 5 2 3 O H C H CCH COOCOCH 6 5 2 3 O H H + C H CCH COOCOCH 6 5 2 3 OH H ? ? ? ? ? O H ? 2 C 6 H 5 CH=CHCOOCOCH 3 ? ? ? ? O H 2 C 6 H 5 CH = CHCO 2 H + CH 3 CO 2 H Haloform reaction : Acetaldehyde and methylalkyl ketones react rapidly with halogen (Cl 2 , Br 2 or I 2 ) in the presence of alkali to give haloform and acid salt. 3 CH C R || O ? ? ? ? ? ? ? ? ? NaOH / Br 2 3 CHBr ONa C R || O ? ? ? (Bromoform) In this reaction ? CH 3 of ? ? C CH || O 3 group is converted into haloform as it contains acidic hydrogen atom and rest-part of alkyl methyl ketone give acid salt having carbon atom corresponding to alkyl ketone. Preparation of haloform from methylketone involves two steps. (a) Halogenation 3 CH C R || O ? ? ? ? ? ? 2 Br 3 CBr C R || O ? ? (Halogenation) (b) Alkalihydrolysis 3 CBr C R || O ? ? ? ? ? ? ? NaOH CHBr 3 + ONa C R || O ? ? (Alkalihydrolysis) Note : This reaction is used to distinguish the presence of ? ? C CH || O 3 group. Other reactions : (1) (2) (3) (4) (5) (6) Page 5 ? Points to remember in Aldehyde & ketone Aldol condensation : Carbonyl compounds having acidic sp 3 ?-H shows this reaction in presence of dil. NaOH or dil. acid. O C CH 2 | H 3 ? ? Dil NaOH ???? H | CHO CH C CH | OH 2 3 ? ? ? O H , H 2 ? ? ? ? ? ? ? ? CHCHO CH CH 3 ? Crossed aldol condensation (i) CH 3 CHO + HCHO ? ? ? ? ? ? ? NaOH . Dil HOCH 2 ?CH 2 ?CHO ? ? ? ? ? ? ? ? O H / H 2 CH 2 =CH?CHO (ii) CH 3 COCH 3 + HCHO ? ? ? ? ? ? ? NaOH . Dil CH 3 CO?CH 2 CH 2 OH ? ? ? ? ? ? ? ? O H / H 2 CH 3 CO?CH=CH 2 Cannizzaro reaction : Carbonyl compounds not having sp 3 ?-H shows following disproportion reaction %) 50 ( NaOH H C H 2 || O ? ? ? ?? ? OH CH 3 ? + HCOONa CHO H C 2 5 6 + %) 50 ( NaOH ?? ? OH CH H C 2 5 6 + benzoate . Sol COONa H C 5 6 Crossed Cannizzaro reaction : + HCHO + %) 50 ( NaOH ?? ? + formate . Sod HCOONa Formation of hydrzones and azines C=O + NH NH 2 2 C NHNH 2 OH ?H O 2 C= NNH 2 CO C= N?N = C Perkin reaction : When benzaldehyde (or any other aromatic aldehyde) is heated with the anhydride of an aliphatic acid (containing two ?-hydrogen atoms) in the presence of its sodium salt, condensation takes place to form a ?-arylacrylic acid ; e.g., with acetic anhydride and sodium acetate, cinnamic acid is formed. C 6 H 5 CHO + (CH 3 CO) 2 O ? ? ? ? ? ? Na CO CH 2 3 C 6 H 5 CH = CHCO 2 H Mechanism : CH 3 COOCOCH 3 + CH 3 CO 2 ? H CO CH COOCOCH H C 2 3 3 2 ? ? C H C + CH COOCOCH 6 5 2 3 O H C H CCH COOCOCH 6 5 2 3 O H H + C H CCH COOCOCH 6 5 2 3 OH H ? ? ? ? ? O H ? 2 C 6 H 5 CH=CHCOOCOCH 3 ? ? ? ? O H 2 C 6 H 5 CH = CHCO 2 H + CH 3 CO 2 H Haloform reaction : Acetaldehyde and methylalkyl ketones react rapidly with halogen (Cl 2 , Br 2 or I 2 ) in the presence of alkali to give haloform and acid salt. 3 CH C R || O ? ? ? ? ? ? ? ? ? NaOH / Br 2 3 CHBr ONa C R || O ? ? ? (Bromoform) In this reaction ? CH 3 of ? ? C CH || O 3 group is converted into haloform as it contains acidic hydrogen atom and rest-part of alkyl methyl ketone give acid salt having carbon atom corresponding to alkyl ketone. Preparation of haloform from methylketone involves two steps. (a) Halogenation 3 CH C R || O ? ? ? ? ? ? 2 Br 3 CBr C R || O ? ? (Halogenation) (b) Alkalihydrolysis 3 CBr C R || O ? ? ? ? ? ? ? NaOH CHBr 3 + ONa C R || O ? ? (Alkalihydrolysis) Note : This reaction is used to distinguish the presence of ? ? C CH || O 3 group. Other reactions : (1) (2) (3) (4) (5) (6) ? Points to remember in Carboxylic acid & Derivative Summary of reactions of carboxylic acids :Read More
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