An optimisation study based upon experimental data obtained from multivaria
te statistical experimental design and modelling for the haloform reaction
used for synthesis of 3,4-dimethoxybenzoic acid from 3,4 dimethoxy acetophe
none is reported. It is shown how the different controllable process variab
les influence both the yield of 3,4-dimethoxybenzoic acid and the formation
of the side product 2-chloro-4,5-dimethoxybenzoic acid. Two predictive mul
tivariate models are derived and used to predict optimal conditions for the
oxidation process, Using these models, a yield of 90% (from approximately
60%) of desired product is achieved, Moreover, the model describing the for
mation of the side-product can in fact also be applied to optimise a proced
ure for obtaining 2-chloro-4,5-dimethoxybenzoic acid in substantial quantit
ies. One experiment showed that the side-product could be formed in a quant
ity of >20%.