Self-Assembly of Hydrogen-Bonded Cage Tetramers of Phosphonic Acid

The self-association of phosphonic acids with general formula RP(O)(OH)2 in solution state remains largely unexplored. understanding is that such molecules form multiple intermolecular hydrogen bonds, but the stoichiometry self-associates and bonding motifs are unclear. In this work, we report results study tert-butylphosphonic acid using low temperature liquid-state 1H 31P NMR spectroscopy (100 K; CDF3/CDF2Cl) density functional theory (DFT) calculations. For first time, demonstrate conclusively polar aprotic medium forms highly symmetric cage-like tetramers held by eight OHO which makes complex quite stable. these associates. each molecule bonded to three other forming two bonds as proton donor acceptor. Though structure close tetrahedral, formal symmetry self-associate C2.