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junior college 1 | H2 Maths
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Ng Wei Lin
Ng Wei Lin

junior college 1 chevron_right H2 Maths

Some one help me explain the ans !! I dont get it !! The answers are D and B

Date Posted: 6 years ago
Views: 464

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Tang Jiacheng
Tang Jiacheng's answer
96 answers (Tutor Details)
1st
The mechinism I have here is probably not correct. The actual mechanism may involve multiple steps/intermediates for example, but the idea is that Br is acting as a nucleophile and attacking the delta positive H atom attached to N, so it is a nucleophilic substitution (Br substituting H).

For the second question, B is the iodoform test, which works for most alcohols which have a methyl group attached to the carbon bonded to OH. It should be clear that phenol cannot give a positive result.
Ng Wei Lin
Ng Wei Lin
6 years ago
I still dn get how the N can go from the left side of the milecule to the middle at the product!

And iodoform test can also be used on carbonyl compound i tot?
Tang Jiacheng
Tang Jiacheng
6 years ago
Yes, but look carefully, the CO in paraceutamol is not a carbonyl group, but an amide right?
Ng Wei Lin
Ng Wei Lin
6 years ago
Oh it can only work of the R grp only contains carbon ??
Tang Jiacheng
Tang Jiacheng
6 years ago
I mean the compound does not even have a carbonyl group. It is an amide group instead (R-CONH-R')...