As is known, quaternary ammonium compounds (also known as "quats") have utility in various applications (e.g., as fungicides, algicides, bactericides, and bleach activators) and can be prepared by reacting tert-amines with suitable quaternizing agents. Different types of materials have been used as quaternizing agents in such reactions, but haloalkanes are apt to be preferred.
Known quaternizations of tert-amines have typically been conducted in organic solvents which must be separated from the product at the end of the reaction, thus increasing costs. European Patent Application 0288857 (Rutzen et al.) shows that the necessity of recovering product from a solvent can be avoided when a tert-amine is quaternized under pressure with an excess of an alkyl halide that is gaseous under the reaction conditions. However, this process has the disadvantages of requiring the recovery, recycling, or disposal of the excess alkyl halide, as well as the use of pressure equipment; and it is not suitable for the preparation of quats in which the quaternizing group has a relatively long chain.