On the deprotonation of 3,5-dichloropyridine using lithium bases: in situ infrared spectroscopic studies

Deprotonation of 3,5-dichloropyridine using LTMP and BuLi was monitored in real time by infrared spectroscopy. It appeared that the substrate was rapidly deprotonated. Transient structures between the substrate and the lithio derivative were detected. The absorbances recorded for the lithio derivative showed that the structures obtained using LTMP and BuLi were similar. When BuLi was used to deprotonate, a complete deuteration of the lithio derivative was noted upon quenching with D₂O. The latter did not allow the quantification of the lithio derivative when LTMP was used, since only partial deuteration was observed.