The application of quantum chemical and statistical technique in developing quantitative structure-property relationships for the photohydrolysis quantum yields of substituted aromatic halides

Based on the nature of the carbon-halogen bond to be broken and the halogen atoms to be replaced in photohydrolysis reactions, the method of factor analysis and cluster analysis was used to group 45 substituted aromatic halides into three clusters. 20 compounds are grouped in Cluster A, which are characterized as substituted bromobenzenes and iodobenzenes. 17 compounds belong to Cluster B, which are characterized as substituted chlorobenzenes; and 8 compounds are grouped in Cluster C, which are characterized as substituted fluorobenzenes. Based on the grouping and the use of quantum chemical descriptors derived from PM3 Hamiltonian, 28 Quantitative Structure-Property Relationships (QSPR) for photohydrolysis quantum yields are obtained. It was shown from these equations that the significant quantum chemical descriptors governing photolysis quantum yields of the three clusters are different from each Other.