Theoretical study of intramolecular hydrogen bond in selected symmetric “proton sponges” on the basis of DFT and CPMD methods

摘要: "Proton sponges," derivatives of prototypic 1,8-bis(dimethylamino)naphthalene (DMAN), exhibit remarkable basicity, which made them interesting for various experimental and theoretical studies. The details bridged proton dynamics in protonated DMAN its derivative denoted as TMGN (1,8-bis(tetramethylguanidino)naphthalene) were investigated on the basis density functional theory (DFT) Car-Parrinello molecular (CPMD) methods. Special attention was paid to effects symmetry skeleton type substituent neighborhood statistics dynamics. metric parameter analyses hydrogen bridge provided us with a conclusion that migration events TMGNH+ are less numerous than DMANH+, can be rationalized by noticing slower large substituents respect smaller -N(Me)2 groups DMAN. atomic velocity power spectra served computational models vibrational signatures associated presence intramolecular bond. A broad feature registered bonds present both compounds. computations verified data available.