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Answer the following.

How will the following be converted? (Give chemical equations) Diethyl ether from sodium ethoxide…

Chemistry20273 marksConversion
How will the following be converted? (Give chemical equations)
(a)[1.0]
Diethyl ether from sodium ethoxide
(b)[1.0]
Propan-2-ol from Grignard’s reagent
(c)[1.0]
Phenol from Cumene

Answer

Answer (a)

Official answer key

Equation: $\mathrm{C_{2}H_{5}ONa} + \mathrm{C_{2}H_{5}Br} \xrightarrow{\text{330}\text{ }\text{K}\text{ }\text{(Williamson}\text{ }\text{synthesis)}} \mathrm{C_{2}H_{5}OC_{2}H_{5}} + \mathrm{NaBr}$

Sodium ethoxide reacts with bromoethane to give diethyl ether.

Answer (b)

Official answer key

Equations: $\mathrm{CH_{3}CHO} + \mathrm{CH_{3}MgBr} \xrightarrow{\text{dry}\text{ }\text{ether}} \mathrm{(CH_{3})_{2}CHOMgBr}$ $\mathrm{(CH_{3})_{2}CHOMgBr} + \mathrm{H_{2}O} \xrightarrow{\text{H+}} \mathrm{(CH_{3})_{2}CHOH} + \mathrm{Mg(OH)Br}$

Ethanal reacts with methylmagnesium bromide, and hydrolysis of the adduct gives propan-2-ol.

Answer (c)

Official answer key

Equations: $\mathrm{C_{6}H_{5}CH(CH_{3})_{2}} + \mathrm{O_{2}} \xrightarrow{\text{air}\text{ }\text{oxidation}} \mathrm{C_{6}H_{5}C(CH_{3})_{2}OOH}$ $\mathrm{C_{6}H_{5}C(CH_{3})_{2}OOH} \xrightarrow{\text{H+}\text{,}\text{ }\mathrm{H_{2}O}} \mathrm{C_{6}H_{5}OH} + \mathrm{CH_{3}COCH_{3}}$

Cumene is oxidised by air to cumene hydroperoxide, which on acid hydrolysis gives phenol and acetone.
Alcohols

From ISC 2027 Specimen Chemistry Paper 1, question 14(ii).