Propene to 1-Iodopropane
To convert propene to 1-iodopropane, hydroiodic acid (HI) is used in an electrophilic addition reaction.
The double bond in propene reacts with HI. According to Markovnikov's rule, the hydrogen atom from HI attaches to the carbon with more hydrogen atoms, and the iodine attaches to the other carbon, forming the desired product.
\( \text{CH}_2=\text{CHCH}_3 + \text{HI} \rightarrow \text{CH}_3\text{CH}_2\text{CH}_2\text{I} \)
Product: 1-iodopropane
Write IUPAC names of the following compounds and classify them into primary, secondary and tertiary amines.
(i) (CH3 )2CHNH2 (ii) CH3 (CH2 )2NH2 (iii) CH3NHCH(CH3 )2
(iv) (CH3 )3CNH2 (v) C6H5NHCH3 (vi) (CH3CH2 )2NCH3 (vii) m–BrC6H4NH2
Give one chemical test to distinguish between the following pairs of compounds.
(i) Methylamine and dimethylamine
(ii) Secondary and tertiary amines
(iii) Ethylamine and aniline
(iv) Aniline and benzylamine
(v) Aniline and N-methylaniline
Account for the following:
(i) pKb of aniline is more than that of methylamine.
(ii) Ethylamine is soluble in water whereas aniline is not.
(iii) Methylamine in water reacts with ferric chloride to precipitate hydrated ferric oxide.
(iv) Although amino group is o– and p– directing in aromatic electrophilic substitution reactions, aniline on nitration gives a substantial amount of m-nitroaniline.
(v) Aniline does not undergo Friedel-Crafts reaction.
(vi) Diazonium salts of aromatic amines are more stable than those of aliphatic amines. (vii) Gabriel phthalimide synthesis is preferred for synthesising primary amines.