Templated heptaborate and pentaborate salts of cyclo-alkylammonium cations: structural and thermal properties
Autor: | Peter N. Horton, Michael A. Beckett, K. Sukumar Varma, Michael B. Hursthouse, James L. Timmis |
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Rok vydání: | 2012 |
Předmět: | |
Zdroj: | Dalton Transactions. 41:4396 |
ISSN: | 1477-9234 1477-9226 |
DOI: | 10.1039/c2dt12310j |
Popis: | The synthesis and characterization of a series of cyclo-alkylammonium pentaborate salts {[cyclo-C(n)H(2n-1)NR(3)][B(5)O(6)(OH)(4)] (R = H, n = 3, 5-7 (1-4); R = Me, n = 6 (5))} are reported. Compounds 1, 2 and 5 have been further characterized by single-crystal XRD studies. Attempted recrystallization of 3 and 4 yielded small crops of the unexpected heptaborate salts, [cyclo-C(6)H(11)NH(3)](2)[B(7)O(9)(OH)(5)]·3H(2)O·B(OH)(3) (6) and [cyclo-C(7)H(13)NH(3)](2)[B(7)O(9)(OH)(5)]·2H(2)O·2B(OH)(3) (7) which were also characterized crystallographically. All compounds show extensive supramolecular H-bonded anionic lattices templated by the cations. H-bond interactions are described in detail. TGA-DSC analysis of the pentaborates 1-5 showed that they thermally decomposed in air at 800 °C to 2.5B(2)O(3), in a 2 step process involving dehydration (250 °C) and oxidative decomposition (250-600 °C). BET analysis of materials derived from the pentaborates had internal porosities of1 m(2) g(-1). |
Databáze: | OpenAIRE |
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