Bromoethane reacts with ammonia as follows.?

Question

Bromoethane reacts with ammonia as follows.
CH3CH2Br + NH3 → CH3CH2NH + Br−
CH3CH2NH + NH3 → CH3CH2NH2 + NH
The mechanism for this reaction is described as SN2.







(a) State the name of the organic product of the reaction, CH3CH2NH2.
.....................................................................................................................................
(b) Explain, using “curly arrows” to show the movement of electron pairs, the mechanism of the attack by ammoniaon bromoethane.

Answer 1

a) CH3CH2NH2 is ethylamine.



b) CH3CH2-Br + :NH3 --> CH3CH2-NH3(+) + Br(-)

CH3CH2-NH3(+) + Br(-) --> CH3CH2-NH2 + HBr



Since I can't use curly arrows here, I'll explain what happens. The lone pair of electrons on the nitrogen atom of ammonia attacks the C-1 center methylene (CH2) group of bromoethane and kicks out Br- which forms the products shown on the first line. Then, the resulting ammonium intermediate (CH3CH2-NH3(+) loses an proton to from the neutral amine (ethyl amine) and HBr.



I'm not sure what the second part of your reaction is supposed to be but it doesn't look correct to me.



Hope this helps!!!

Answer 2

a. ethylamine

b. curly arrows drawn from the H2C-Br bond to the electron pair in NH3



The question format looks familiar. Is it an I.B. Chem question?

Answer 3

Bromoethane