Primary aliphatic amine with halogenoalkanes

• The reaction between butylamine (primary aliphatic amine) and a halogenoalkane produces a secondary amine and hydrogen halide.
• Butylamine (primary aliphatic amine) can react with a halogenoalkane because the halogenoalkane contains an electron-deficient carbon atom and an amine contains an electron-rich nitrogen atom.
• The standard equation for the reaction between a primary aliphatic amine and a halogenoalkane is : R1NH2 + R2X -> R1NHR2 + HX. R1 is the alkyl group in the amine, while R2 is the alkyl group in the halogenoalkane.
• The reaction between butylamine (primary aliphatic amine) and a halogenoalkane is a substitution reaction, and produces a secondary amine and a hydrogen halide.
• The first reaction between butylamine and chloroethane produces a secondary amine and hydrogen chloride. The secondary amine possesses an electron-rich nitrogen atom, so it can react further in chloroethane.
• Once the secondary amine has been formed, it can react in excess chloroethane. This reaction produces a tertiary amine and hydrogen chloride. The tertiary amine also possesses an electron-rich nitrogen atom, so can react further in chloroethane.
• After the formation of the tertiary amine, it can react further in chloroethane. This produces a quaternary ammonium salt (NH4+ and Cl-), however the inorganic product is not hydrogen chloride. This is because the tertiary amine doesn't have a hydrogen to lose from the nitrogen atom.
• The reaction of butylamine (primary aliphatic amine) with halogenoalkanes is not a good method for producing a secondary amine. This is because if the halogenoalkane is in excess, the sequence of all four reactions is more likely to occur.