Altius 4 C/P #35

[salemstein]

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I'm kinda confused why B is the answer. Wouldn't treating compound 6 with base first deprotonate the -OH, since the oxygen can hold the negative charge better than nitrogen? Don't you need a protecting group or something?

 

[Sai111394]

The NH2 is an electron donating group, so no, oxygen would not be able to hold the negative charge better. The NH2 group will do a nucleophilic attack on the carbonyl group with chloride as the leaving group. Now the nitrogen will have a +1 charge so the base will deprotonate and there will be another electron to attack the other chloride and have it leave. hope that makes sense.

 

[AnonPanda1]

The NH2 is an electron donating group, so no, oxygen would not be able to hold the negative charge better. The NH2 group will do a nucleophilic attack on the carbonyl group with chloride as the leaving group. Now the nitrogen will have a +1 charge so the base will deprotonate and there will be another electron to attack the other chloride and have it leave. hope that makes sense.

This guy is right. Also, the yield is 80%. You are right that the deprotonation would cause side products to form.

 

[Sai111394]

This guy is right. Also, the yield is 80%. You are right that the deprotonation would cause side products to form.

Right. You could go as far to say that after the first nucleophilic attack, now the nitrogen has an electron withdrawing group, so the oxygen could get deprotonated because now the oxygen could handle the negative charge better, and cause side products.