Organic Chemistry5

Question 1
--------NaNH2,NH3------->-----CH3I------>

Please write steps.

----------------------------------------------------------------------------------------

Question 2
----MeI-->---Ag2O,H2O---->---\Delta------>

Please write steps.

------------------------------------------------------------------------------------

Question 3
---75.C---->----(CH3)3COH---->

TRUE/FALSE Type:
Major product is Less Substituted alkene and Minor Product is more substituted alkene.

13 Answers

39
Pritish Chakraborty ·

Tapas in Q2 where is the nitrogen group? If it's supposed to be Hoffmann elimination..
In Q3, both substrate and base are bulky, and temperature also suits elimination. So ans is an alkene?
TRUE...base is bulky..HOFFMAN KI JAI LOL :D

1
Tapas Gandhi ·

@Pritish sorry!!!! x2
edited.x2 (see Q3 now)

39
Pritish Chakraborty ·

As it is a C-C single bond, in Q2, rotation will take place to make H anti to the leaving N+Me3 group. Product will be C(Ph wedge)(CH3 dashed) = C(CH3 wedged) (H dashed)

1
Tapas Gandhi ·

@pritish: Can u state wat the reagents do? pls. (in each q u kno)

39
Pritish Chakraborty ·

See CH3I is simple. Nitrogen is nucleophilic as long as it has its lone pair, and it will substitute CH3I in an SN2 reaction. If the nitrogen atom does not have any protons to lose (to regain its lone pair) it becomes positively charged, that is, a quarternary nitrogen. This fact is exploited because a quarternary nitrogen is a good leaving group. Now usual elimination takes place, E2 style(antiperiplanar) but without Zaitsev Rule.

1
Ankur ·

for Q1: I think:

1
Tapas Gandhi ·

Q1 Answer:
Ankur u 'seem' to be wrong

Q2: SOLVED (ans is correct)- thx pritish and govind

Q3 Answer: FALSE. Justify???

39
Pritish Chakraborty ·

Tapas I meant for normal Hoffmann elimination...Elimination cannot take place in pyridine obviously.

1
Tapas Gandhi ·

ok u meant q2 (i see). i stand corrected.

1
Tapas Gandhi ·

REG Q3

The less substituted product shown was:

39
Pritish Chakraborty ·

Yes Tapas thats the least substituted alkene I thought of...bulky bases produce such namuneys(samples). What's wrong with that?

1
Tapas Gandhi ·

it is NOT the major product as ans is false>>

39
Pritish Chakraborty ·

Can you explain why the answer is such?

Your Answer