Assembly of Hybrid Organic–Organometallic Materials through Mechanochemical Acid–Base Reactions

摘要: Manual grinding of the organometallic complex [Fe(η5-C5H4COOH)2] with a number solid bases, namely 1,4-diazabicyclo[2.2.2]octane, C6H12N2, 1,4-phenylenediamine, p-(NH2)2C6H4, piperazine, HN(C2H4)2NH, trans-1,4-cyclohexanediamine, p-(NH2)2C6H10, and guanidinium carbonate [(NH2)3C]2[CO3], generates quantitatively corresponding adducts, [HC6H12N2][Fe(η5-C5H4COOH)(η5-C5H4COO)] (1), [HC6H8N2][Fe(η5-C5H4COOH)(η5-C5H4COO)] (2), [H2C4H10N2][Fe(η5-C5H4COO)2] (3), [H2C6H14N2][Fe(η5-C5H4COO)2]⋅2 H2O, (4⋅2 H2O), [C(NH2)3]2[Fe(η5-C5H4COO)2]⋅2 H2O, (5⋅2 H2O), respectively. Crystallization from methanol in presence seeds ground sample allows growth single crystals these adducts; therefore we were able to determine structures adducts by single-crystal X-ray diffraction. This information was used turn identify characterize polycrystalline materials obtained process. In case [HC6N2H12][Fe(η5-C5H4COOH)(η5-C5H4COO)] base can be removed mild treatment regenerating starting dicarboxylic acid, while all other cases decomposition is observed. The solid–solid processes described herein imply molecular diffusion through lattice, breaking reassembling hydrogen-bonded networks, proton transfer acid base.