Previously, an 'additivity' equation relating experimental 13C chemical shift data for two mono-substituted diphenyl-1,3-thiazolidin-4-one series was developed to predict chemical shifts for a similarly substituted bis-disubstituted thiazolidinone series. The sites of interest in the 1,3-thiazolidin-4-one are the C-2, C-4, and C-5 carbons. The empirically derived equation for predicting the chemical shifts is □xy= □h + (□x-□h) + (□y- □h) where □xy is the predicted chemical shift for the disubstituted thiazolidinone, □h is the experimental chemical shift for the unsubstituted thiazolidinone, □xDx is the experimental chemical shift for substituent in the 2-phenyl ring, and □y is the experimental chemical shift for substituent in the N-(3)-phenyl ring. This article discusses the application of the aforementioned equation with respect to a new series of substituted-2-phenyl-3-methoxyphenyl-1, 3-thiazolidin-4-ones, where the substituents on both phenyl rings are not the same. The equation was shown to predict a less exact chemical shift in this one test series than for the previous bis-disubstituted series of compounds.
All Science Journal Classification (ASJC) codes
- Organic Chemistry