(399e) Triflation Reaction Endpoint By A T R - F T I R, P L S - Based Chemometrics Model

In-situ ATR-FTIR was used to monitor triflation of reactant R-OH with trifluoromethanesulfonic anhydride at -35 ºC to -50 ºC in a batch reactor. Data from three triflations were sufficient to evaluate models to correlate the spectral first derivatives with residual starting material levels derived from HPLC analyses. Approaches evaluated included simple linear regression, multiple regression, and full multivariate partial least squares (PLS). Spectral data collected in a fourth run was input to the PLS model, and the predicted residual R-OH levels compared favorably with the HPLC values. An updated PLS model was then generated by including data collected from all four batch reactions at -50 ºC. The refined model was used to predict starting material levels in real-time in a subsequent triflation, predicting down to levels as low as 1 PA% ± 1 PA%.