title: The Synthesis of Organic Molecules of Intrinsic Microporosity Designed to Frustrate Efficient Molecular Packing.
abstract: Efficient reactions between fluorine-functionalised biphenyl and terphenyl derivatives with catechol-functionalised terminal groups provide a route to large, discrete organic molecules of intrinsic microporosity (OMIMs) that provide porous solids solely by their inefficient packing. By altering the size and substituent bulk of the terminal groups, a number of soluble compounds with apparent BET surface areas in excess of 600 m(2)  g(-1) are produced. The efficiency of OMIM structural units for generating microporosity is in the order: propellane>triptycene>hexaphenylbenzene>spirobifluorene>naphthyl=phenyl. The introduction of bulky hydrocarbon substituents significantly enhances microporosity by further reducing packing efficiency. These results are consistent with findings from previously reported packing simulation studies. The introduction of methyl groups at the bridgehead position of triptycene units reduces intrinsic microporosity. This is presumably due to their internal position within the OMIM structure so that they occupy space, but unlike peripheral substituents they do not contribute to the generation of free volume by inefficient packing.
authors.affiliation: School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK.
authors.forename: Rupert G D
authors.initials: RG
authors.lastname: Taylor
authors.affiliation: EaStCHEM School of Chemistry, University of Edinburgh, David Brewster Road, Edinburgh, EH9 3FJ, UK.
authors.forename: C Grazia
authors.initials: CG
authors.lastname: Bezzu
authors.affiliation: EaStCHEM School of Chemistry, University of Edinburgh, David Brewster Road, Edinburgh, EH9 3FJ, UK.
authors.forename: Mariolino
authors.initials: M
authors.lastname: Carta
authors.affiliation: EaStCHEM School of Chemistry, University of Edinburgh, David Brewster Road, Edinburgh, EH9 3FJ, UK.
authors.forename: Kadhum J
authors.initials: KJ
authors.lastname: Msayib
authors.affiliation: School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Walker
authors.affiliation: School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK.
authors.forename: Rhys
authors.initials: R
authors.lastname: Short
authors.affiliation: School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK.
authors.forename: Benson M
authors.initials: BM
authors.lastname: Kariuki
authors.affiliation: EaStCHEM School of Chemistry, University of Edinburgh, David Brewster Road, Edinburgh, EH9 3FJ, UK. neil.mckeown@ed.ac.uk.
authors.forename: Neil B
authors.initials: NB
authors.lastname: McKeown
keywords: adsorption; aromatic nucleophilic substitution; microporous materials; molecular packing; triptycene