Aldehdydes, ketones, carboxylic acids & amines Dr/ Nabila Al-Jaber Professor of Chemistry, King Saud University

Aldehydes & ketones C n H 2n O (+)C=O(-) polar react with acid and base

Nomenclature: A] Aldehyde 1] Ald. up to 4 c by common name of the acids to which they related. 2] More than 4 by replacing e(from alkane) by –al. 3] C of ald. Always No. 1 (not appear in the name) CH 3 CH 2 CH 2 CHO (IUPAC: Butanal / Comm. Butyraldehyde)

Nomenclature: 4] Substituted ald. By alphabet. If (OH > C=C or C  C ) ClCH 2 CH 2 CH 2 CH 2 CHO CH 3 CH 2 CH=CHCHO CH 3 CHOHCHClCH 2 CHO 5-Chloropentanal 2-Pentenal 3-Chloro-4-hydroxy pentanal

5] Aromatic aldehyd derivatives of simplest aromatic (bezald.)

B] Ketones 1) Simple by alkyl substituent and word ketone

2] complicated ketones by IUPAC by replacing (e) by(-one) (in longest cont. chain with C=O) ket. Take lower no. CH 3 CH 2 COCH 3 CH 3 COCH 2 CH 2 CH 2 CH3 CH 3 CH 2 COCH 2 CH 2 CH 3 CH 3 CH 2 CHClCOCH 2 CH 3 CH 3 CH 2 CH=CHCOCH 3 3-hexene-2-one Butanone 2-Hexanone 3-hexanone 4-chloro-3-hexanone

3] If position of C=O not clear no. is needed for no. CH 3 CH 2 CH=CHCOCH 3 3-hexene-2-one

Physical Properties. -Simple (1-6) ald. & keto. Soli. in H 2 O - If R (inc) soli. (dec.) - more than 6 C insole. Dipole- dipol attractions Solubility B.P ald &ket. > alkane (same m.wt) Boiling point C=O polar, So Ald. & ket Polar (intermolecular attraction)

Preparation of Aldehydes & ketones 1] Oxidation of 1  & 2  alcohol : 2] Ozonolysis of alkenes:

Preparation of Aldehydes & ketones 3] Hydrolysis of alkynes: HC ≡ CH+ H 2 SO 4 aldhyde

4] Friedel Craft acylation:

Reactions of Aldehydes and ketones 1] Addition of metal hydrides( formation of alcohol)

Reactions of Aldehydes and ketones 1] Addition of metal hydrides( formation of alcohol) 0 0 0

2] Reactions with Grignard reagent:

o

3]Addition of alkynide ions: {R-C ≡ C(-)} +

4]Addition of hydrogen cyanide (cyanohydrins formations):

cyanohydrins formations

+

5] Addition of alcohols Ald.. + alcoh. — H+--- hemiacital Ket. + alcoh. — H+--- hemiketal a) Hemiacitals formation

b) Hemiketals formation 5] Addition of alcohols

c) Acetal formation:

d) Ketal formation: OH

6] Addition of ammonia and it's derivatives

Reduction of oxime

7] Iodoform reaction

8]Aldol condensation: Aldehydes

Ketones 8]Aldol condensation:

Carboxylic acid R-COOH Ar-COOH Aliphatic (carboxylic cid) aromatic (benzoic acid) 1) replace ane by -ic acid Nomenclature : CommonIUPACFormula No. C Formic acid Acetic acid Prpionic acid Butyric acid valeric acid Salicylic acid Benzoic acid Methanoic acid Ethanoic acid Prpanoic acid Butanoic acid Pentanoic acid 2-hydroxy ben. a HCOOH CH 3 COOH CH 3 CH 2 COOH CH 3 (CH 2 ) 2 COOH CH 3 (CH 2 ) 3 COOH 12345

2) Longest continuous chain CH 3 CH 2 CHCH 2 CH 2 COOH 4-Methyl hexanoic acid CH 3      C-C-C-C-C-COOH commmone:  -  - Dimethyl butyric acid IUPAC: 2,3-Dimethyl butanoic a CH 3 -CHBr-CHCl-CO 2 H 3-Bromo-2-chlorobutnoic acid CH 3 CH 2 CHCH 2 CH 2 COOH γ-Methyl hexenoic acid CH 3

3) In cyclic ring cycloalkane carb. a'

4) Aromatic acid by common name

Physical properties: 1] They form hydrogen 2] comp. 1-7 soli in H 2 O. 3] mor than 7 carbon less soli. (bec. R increased) 4] Aromatic acids insoluble. In H 2 O 5] BP. Acid > Alcohol

Acidity Deac. gps inc. acidity Acti gps dec. acidity

HCOOH > CH 3 COOH > CH 3 CH 2 COOH > CH 3 CH 2 CH 2 COOH More acidity Substitution with halogen : CH 3 CH 2 COOH CH 2 Cl-CH 2 COOH (more acidic) CH 3 CH 2 COOH < CH 2 Cl-CH 2 COOH (more acidic) CH 3 CH 2 COOH < CH 2 ClCOOH < CHCl 2 COOH < CCl 3 COOH More acidity

Preparation of carboxylic acid 1] Oxidation a) 1  alcohols & Aldehydes

b) of alkyl benzene

2)Hydrolysis of nitriles

3] Carbonation of Grignard reagent:

Reactions of acids 1)Salt formation: it react with strong base & we can use Ca or K It reacts with weak base Sodium bicarb. Can be used to distinguish between carboxylic acid and phenols

2) Formation of Easter: 3) Formation of amide: 4) Formation of acid anhydride: 5) Formation of acid chloride:

Nomenclature of carboxylic acid derivatives When Oxygen of Carboxylic acid is replaced with Nu Carb. a' deriv

1] Salt: 2] Acid chloride

4] Ester: The alkyl gp. Named 1st then the name of parent acid with ending – ate in place of -ic acid

4]Amides: -oic acid or -ice a' by – amide.f 1 or 2 subst. on nitrogen we say N-subs. or N,N-disubs. (sub. Name 1st )

4] Acid anhydride: replacing -acid with anhydride R-CO-Cl > R-(CO) 2 O-R > RCO 2 R > RCO 2 H > RCONH 2 Acid chloride Acid anhydride Ester Acid Amide Order of reaction:

Reactions of acid derivatives a) Acid chlorides: Reduction:

B] Acid anhydride: Reduction:

C] Esters: Reduction:

d] Amide: Reduction: Dehydration: Hoffman degradation:

Amines - Intermediate in organic chemistry reactions -Amino acids (proteins DNA, RNA) -Alkaloids and drugs It is derived from ammonia by replacing 1,2 or three H by alkyl or aryl gp. -Aliphatic amines contain only alkyl gps. bonded directly to nitrogen atom. -Aromatic – one or more aryl gps. bonded to N. Structure and classification of Amines:

Aliphatic amines Aromatic amines -1 , 2  &3  or quaternary ammonium salt according to (R) or (Aryl) gp. attached to N atom. + X

Nomenclature of amines 1] Simple aliphatic by alphabetical order to gp. Attached to N and adding -amine

2] Complicated amine we consider (NH)as substituent & it's position will take the lowest possible number.

3] Amine salt by replacing Amine by ammonium 4]Aromatic amine e

Physical properties: - Amines are solutions are basic (ammonia or died fish odor) - 1-3(methyl, dimethyl trimethy) are gases (aliphatic only)- - 1 , 2  amine can form H bond So their MP > alkane of similar M.Wt (B.P Amine > Alkane) Basicity of amines: -Amines basic because N has non bonded pair of electrons which can be donated to an acid to form ammonium salt. - base strength depend on the degree of substitution on N. - More basic CH 3 -NH-CH 3 > NH 2 -CH 3 > NH 3

- Activating gps. Increase basic properties. - RNH 2 > ArNH 2 aliphatic more basic than aromatic - Amine > RCONH 2 (Amide) less basic from amine

Preparation of amines: 1] Reduction of: a) nitro compounds b) Of Amide

c) Of Imines d) Of Oxime : e)Of nitriles

2] Alkylation of Ammonia

3] Hofmann degradation of amides

Reactions of amines 1] With acid chloride acid chloride react with 1  & 2  amine only(no 3  )

Reactions of Diazonium salt: yellow azocompound