Deprotonation of bis(2,4-dinitrophenyl)methane (C-acid 1) and 2,4-dinitrophenyl-2,4,6-trinitrophenylmethane (C-acid2 ) by 7-methyl-1,5,7-triazabicyclo[4,4,0]dec-5-ene (MTBD) and 1,5,7-triazabicyclo[4,4,0]dec-5-ene (TBD) in acetonitrile has been studied using 1 H and 13 C NMR as well as FT-IR spectroscopy. The 1:1 mixtures of N-bases with C-acids form protonated N-bases and products, for which only one respective structure was found. In the case of deprotonated C-acid 1 a symmetrical charge distribution in the phenyl rings was found, whereas for deprotonated C-acid2 the charge distribution was asymmetrical. The spectral feature was explained as a strong electrostatic interaction between the product and the protonated N-bases. The kinetics of the proton transfer reaction from C-acid 1 and C-acid 2 to MTBD and TBD in acetonitrile are reported. The activation parameters are discussed in two aspects: the steric effect of the basic centre and the delocalization of charge for the carbanion products.
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