(a) How will you convert methyl bromide to dimethylamine?
(b) How will you prepare propanamine from methyl chloride using suitable reactions?

Question

Ryan Andrews · Accepted Answer

#"a)"# React it with excess #"NH"_2"CH"_3#, ethanol and #"NaOH"#
#"b)"# I'm not sure how to make propyl amine from methyl chloride, unless you are talking about #N#-methylethylamine. If you are, it's the same process as in #"a)"#, except that the reactant is #"C"_2"H"_5"NH"_2#.

Nucleophilic substitution reactions can be used to synthesize amines from haloalkanes. The result of these reactions is an ammonium salt, which reacts with alkali to produce an amine. To prevent the haloalkane from converting to alcohol, ethanol is employed as a solvent. #"a)"# #"CH"_3"Br"+"NH"_2"CH"_3 rarr "CH"_3"NH"_2"CH"_3^+"Br"^-# #color(white)(a) # #"CH"_3"NH"_2"CH"_3^+"Br"^(-)+"NaOH" rarr "CH"_3"NH""CH"_3+"NaBr"+"H"_2"O"#

Zoe Alexander · Answer

undefined (a) Methyl bromide can be converted to dimethylamine through a two-step process. First, methyl bromide reacts with sodium hydroxide (NaOH) to form sodium bromide (NaBr) and methanol (CH3OH) via an SN2 nucleophilic substitution reaction. Next, methanol undergoes a reaction with ammonia (NH3) in the presence of a catalyst such as aluminum oxide (Al2O3) or zinc oxide (ZnO) at elevated temperatures to yield dimethylamine (CH3NHCH3).

(b) Propanamine can be prepared from methyl chloride through a two-step process. First, methyl chloride undergoes nucleophilic substitution with ammonia (NH3) in the presence of excess ammonia and a catalyst such as iron (III) chloride (FeCl3) or silver nitrate (AgNO3) to form methylamine (CH3NH2). Next, methylamine reacts with chloropropane (C3H7Cl) through a nucleophilic substitution reaction, replacing the chlorine atom with an amino group to yield propanamine (CH3CH2CH2NH2).

(a) How will you convert methyl bromide to dimethylamine? (b) How will you prepare propanamine from methyl chloride using suitable reactions?