Acyl Goup

IUPAC & GOC of Class 12

(i) Naming Acyl Groups- Acid halide and Anhydrides

The group obtained from a carboxylic acid by the removal of the hydroxyl portion is known as an acyl group. The name of an acyl group is created by changing the - ic acid at the end of the name of the carboxylic acid to –yl, examples:

Acyl Goup

(a) Acid Halide

IUPAC name of acid halide is alkanoyl halide.

Acyl Goupwhere X may be Cl, Br, I

Acid chlorides are named systematically as acyl chlorides.

Acyl Goup

(b) Acid anhydride

An acid anhydride is named by substituting anhydride for acid in the name of the acid from which it is derived.

Acyl Goup

Acyl Goup

IUPAC name of acid anhydride is alkanoic anhydride.

Acyl Goup

Example:

Acyl Goup

Butanoic, ethanoic anhydride

(ii) Naming Salts and Esters

General formula of ester RCOOR′

Acyl Goup

IUPAC name:  Alkyl alkanoate

Example:

CH3COOC2H5  (Ethyl ethanoate)

The name of the cation (in the case of a salt) or the name of the organic group attached to the oxygen of the carboxyl group (in the case of an ester) precedes the name of the acid.

Acyl Goup

(iii) Name of Amides and Imides

The names of amides are formed by replacing –oic acid (or –ic acid for common names) by amide or –carboxylic acid by carboxamide.

IUPAC name of acid amide is alkanamide

Acyl Goup

Example:

Acyl Goup

If the nitrogen atom of the amide has any alkyl groups as substitutents, the name of the amide is prefixed by the capital letter N; to indicate substitution on nitrogen, followed by the name(s) of alkyl group(s).

Acyl Goup

If the substituent on the nitrogen atom of an amide is a phenyl group, the ending for the name of the carboxylic acid is changed to anilide

Acyl Goup

Some dicarboxylic acids form cyclic amides in which two acyl groups are bonded to the nitrogen atom. The suffix imide is given to such compounds.

Acyl Goup

8. AMINE

Nomenclature of amines

Nomenclature of amines is quite simple. Aliphatic amines are named by naming the alkyl group (or) groups attached to nitrogen , and following that by the word amine.

Acyl Goup

More complicated amines are often named as prefixing amino - (or-N-methylamino -, N-N, diethyl  amino -, etc) to the name of the parent chain.

Acyl Goup

Aromatic amines - those in which nitrogen is attached to an aromatic ring - are generally named as derivatives of the simplest aromatic amine, aniline.

Acyl Goup

Acyl Goup

Salts of amines are generally named by replacing - amine by - ammonium (or - aniline by - anilinium), and adding the name of the anion.

Acyl Goup

9. NITRO ALKANE

General formual CnH2n+1.NO2

Acyl Goup

Nitro alkane

Example:

Acyl Goup

 

Acyl Goup



2 nitro 3, 3 dimethyl pentane

Alkyl nitrites

Common name is alkyl nitrite there is no IUPAC name of nitrite.

R – O – N = O Alkyl nitrite

CH3CH2 – O NO Ethyl nitrite

10. ALKYL CYANIDE

R – C ≡ N Alkane nitrile

Example:

CH3 – C ≡ N Ethane nitrile

Acyl Goup



2 methyl propane nitrile

Alkyl iso cyanide   RNC

Acyl Goup

Alkyl iso nitrile or alkyl iso cyanide.

There is no specific IUPAC name for alkyl iso cyanide or isonitrile.

CH3NC Ethyl isonitrile

When a compound contains more than one functional group, the numbering and the suffix in the name of multifunctional compound are determined by nomenclature priority.

Preference Order

Class

Formula

Suffix

(if present as a functional group)

Prefix

(if present as a substituent)

Carboxylic acid

Acyl Goup

−oic acid

Carboxy

Acid ahydrides

Acyl Goup

−oic anhydride

 

Eaters

Acyl Goup

Alkyl alkanoate

Alkoxycarbonyl

Acyl halides

Acyl Goup

−oyl halide

Haloalkanoyl

Amides

Acyl Goup

-amide

Carbamoyl

Nitriles

− C ≡ N

Nitrile

Cyano

Aldehydes

Acyl Goup

−al

Formyl

Ketones

Acyl Goup

−one

Oxo

Alcohols

−OH

−ol

Hydroxy

Amines

Acyl Goup

Amine

Amino

Etehrs

− O −

Alkoxy alkane

−oxy

Alkenes

Acyl Goup

−ene

Alkenyl

Alkynes

− C ≡ C −

-yne

Alkynyl

Halides

−X

Halo

Nitro

−NO2

Nitro

Alkanes

Acyl Goup

−ane

Alkyl

Benzene

Acyl Goup

Benzene

Phenyl

Talk to Our counsellor