Doubt 1

JEE Mains 2015 Help › Organic Chemistry questions › Doubt 1

The OH group of methyl alcohol cannot be replaced by chlorine by the action of
(a) Cl ₂ (b) H Cl (c)P Cl ₃ (d) P Cl ₅

#Chemistry #Organic Chemistry

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9 Answers

39

Pritish Chakraborty ·2009-11-21 05:38:24

Cl₂, it is an addition agent, not a substitution agent.

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1

Little Angel ·2009-11-21 05:44:53

Answer is (c)

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39

Pritish Chakraborty ·2009-11-21 05:59:01

Can't be. PCl₃ works for all alcohols which are not sterically hindered, as in presence of pyridine it gives S_N2 reaction.

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Little Angel ·2009-11-21 06:02:05

okay Pritish, I trust u .
Anyways thankyou [4]

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39

Pritish Chakraborty ·2009-11-21 06:17:24

Yes you're right, this is when pyridine is not used. S_Ni occurs like you have said!

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19

Debotosh.. ·2009-11-21 06:24:35

i feel (a)

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3

msp ·2009-11-21 07:50:17

see some energy is needd to break cl-cl which is quite strong,so the given rxn with a is energetically not favoured.

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106

Asish Mahapatra ·2009-11-21 07:54:29

then (accordin to u) answer should be none of these.

But halogens can be added to a double bond system.
It involves breaking of the bond between tem.

Cl2 --> chloronium ion.
Again the other ion adds anti (wise) to form the trans vicinal alkane

so it is (a)

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Kartik Sondhi ·2009-11-26 07:43:30

Cl₂ because Cl₂ cannot reduce as it work is to oxidise

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Your Answer

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