Electronic structure of Alcohols:-

(i) In alcohols both oxygen and the carbon attached to it are sp3 hybridized

(ii) Two of the four sp3 hybridized orbitals of oxygen overlaps separately with l0 orbital of H and an sp3 orbital of carbon of alkyl group to form OH and C – O bond

Electronic structure of Alcohols

 

Methods of preparation of alcohols:-

From Haloalkanes:- when HaloAlkanes (alkyl halides) are heated with aqueous sodium or Potassium Hydroxide, they forms alcohols

Haloalkanes

From Alkenes:- Alcohols can be produced from Alkenes by their Hydration, by passing alkenes through concentrated H2SO4 and then hydrolysis with boiling water gives alcohols.
Mechanism: – it involves following steps

(i) Electrophilic attack by hydroxyl union on alkenes gives a carbocation intermediate :-

Electrophilic attack by hydroxyl

(ii) Nucleophilic attack by water on 20 carbocation

Nucleophilic attack by water

(iii) Deprotonation or loss of proton to form alcohol

Hydroboration – oxidation :- B2H6 (Diborane) if C- deficient molecule it acts as an electrophilic and react with alkenes to form trialkylborates  which on subsequent oxidation with alkaline H2O2 gives alcohols

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