What happens when Propanone is treated with methylmagnesium iodide and then hydrolysed,

The given reaction is an example of the preparation of alcohol. Alcohols are produced by the reaction of Grignard reagents, The first step of the reaction is the nucleophilic addition of Grignard reagent to the carbonyl group to form an adduct. Hydrolysis of the adduct yields alcohol with aldehydes and ketones. Propanone reacts with methyl magnesium iodide to form an adduct which is hydrolyzed to form tertiary butyl alcohol. CH 3 - CO - CH 3 + CH 3 MgI → CH 3 3 C - OMgI → H 3 O + CH 3 3 COH

Predict the reagent for carrying out the following conversions : Phenol to 2,4,6-tribromophenol

Phenols undergo electrophilic substitution reactions. The - OH group attached to the benzene ring activates it towards electrophilic substitution. Also, it directs the incoming group to ortho and para positions in the ring as these positions become electron rich due to the resonance effect caused by - OH group. Thus, phenol can be converted to 2,4,6-tribromophenol by reacting it with bromine water. Bromine atoms are substituted at ortho and para positions of phenol.

Predict the reagent for carrying out the following conversions : Anisole to p-bromoanisole

Anisole can be converted to p-bromoanisole by reacting it with bromine ( Br 2 ) in presence of ethanoic acid. This is an electrophilic substitution reaction. The methoxy group present in anisole donates its electron density of the oxygen atom to the ortho and para position of benzene ring resulting in formation of p-bromoanisole (major) and o-bromoanisole (minor).

Predict the reagent for carrying out the following conversions : Phenol to benzoquinone

Phenol can be converted to benzoquinone by oxidation of phenol with acidified potassium dichromate ( Na 2 Cr 2 O 7 ) . Benzoquinone is a conjugated diketone. In the presence of air, phenols are slowly oxidised to dark coloured mixtures containing quinones.

Give the mechanism for the formation of ethanol from ethene.

Alkenes react with water in the presence of acid as catalyst to form alcohols. Mechanism for the formation of ethanol from ethene: Step 1: Electrophilic attack on the hydronium ion takes place which pronates the ethene to form a carbocation. Step 2: In the second step, the carbocation is attacked by the water molecule. Step 3: The deprotonation lastly generates the ethanol.

Carry out the following conversions : Propene to propanol

Propene can be converted to propanol by acid catalysed hydration. Propene reacts with water in the presence of acid as catalyst to form propanol. A carbocation is formed as an intermediate in this reaction. Mechanism of the reaction: Step 1: The propene reacts with an hydronium ion to generate a 2 ° carbocation. Step 2: In this step, the 2 ° carbocation reacts with the water mole generating a protonated alcohol. Step 3: In this step protonated alcohol reacts with the water molecule generating the product Propan-2-ol. CH 3 CH = CH 2 → H 2 O H + CH 3 CH ( OH ) CH 3

Carry out the following conversions : t-butylchloride to t-butyl ethyl ether

Conversion of t-butylchloride to t-butyl ethyl ether: Step 1: React t-butylchloride with aqueous NaOH to form t-butylalcohol. In presence of alkali, t-butyl alkoxide ion (t-butoxide) is formed. Step 2: Perform Williamson synthesis reaction. In this method, an alkyl halide is allowed to react with sodium alkoxide to form ether. Thus, react ethylbromide with t-butoxide to form t-butyl ethyl ether. ( CH 3 ) 3 CCl + NaOH ( aq ) → ( CH 3 ) 3 COH → Na ( CH 3 ) 3 CONa → C 2 H 5 Cl ( CH 3 ) 3 COC 2 H 5

Carry out the following conversions : Phenol to Salicylaldehyde

Phenol can be converted to Salicylaldehyde by Reimer - Tiemann reaction. In this phenol is treated with chloroform in the presence of sodium hydroxide, and a - CHO group is introduced at ortho position of benzene ring. The intermediate substituted benzal chloride is hydrolysed in the presence of alkali to produce salicylaldehyde.

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Write the structures of products formed when anisole is treated with $HI$ .

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