Spectroscopic studies of the 1:1 complexes of 4-nitrophenyl[bis(ethylsulfonyl)]methane and phenyl[bis(ethylsulfonyl)]methane with 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene and 1,5,7-triazabicyclo[4.4.0]dec-5-ene

The 1:1 complexes of 4-nitrophenyl[bis(diethylsulfonyl)]methane (CH1) and phenyl[bis(diethylsulfonyl)]methane (CH2) with 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) and 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD) have been synthesized and their structures have been studied using the FT-IR, 1H NMR and PM5 semiempirical methods. In all complexes a proton has been transferred from C–H acid to TBD or MTBD molecules to yield ionic pairs. On the basis of the FT-IR and 1H NMR studies of the MTBD complexes, in acetonitrile, the ions have been shown to be fully dissociated. In the case of TBD formation of non-cyclic hydrogen bonded structures have been proposed for the complex being partially dissociated. The calculated structure of the CH2–TBD complex has shown very high similarity to the structure in the solid state.