Online monitoring by infrared spectroscopy using multivariate analysis – background theory and application to catalytic dehydrogenative coupling of butanol to butyl butyrate

The monitoring of chemical reactions can be arduous especially when sampling is required with highly reactive compounds. Online spectroscopic methods provide efficient and non-invasive ways to record the composition of reactive mixtures, yet their use is often limited by the interpretation of spectroscopic data. Herein, we report an easy access and reproducible method for the online analysis of organic transformations through FTIR spectroscopy. Spectra are treated with a multivariate approach to lead to the accurate quantification of the chemicals involved. Further, the technique was applied to the acceptorless dehydrogenation coupling (ADC) of alcohol and allows the first in situ quantitative assessment of the aldehyde intermediate.