Bruce M. Foxman
Professor of Chemistry Emeritus
Iowa State University, Chemistry, BS
Massachusetts Institute of Technology, PhD
When two or more small molecules combine in a crystal, unusual opportunities may arise. The rewards that result from such opportunities include chemo-, stereo- and enantiospecific syntheses, the synthesis of polymer single crystals, and the facile preparation of otherwise-unattainable molecules. Beyond the rewards lies a challenge: the discovery and design of new classes of materials capable of solid-state reactivity, and the elucidation of the principles which govern their behavior. Pursuit of this goal requires knowledge of molecular solid-state chemistry, principles of crystal packing, and chemical reactivity. Salts and complexes of metals with pendant unsaturated carboxylates provide a set of reactive centers which may be proximate in the solid state. In favorable cases, a set of "favorable" intermolecular contacts will satisfy the criteria for the onset of solid state reactivity, viz., that unsaturated groups be oriented in a parallel fashion, at distances ca. 4.2 Å from one another. Recent studies also include: (a) discovery of new polymorphs of important pharmaceuticals, (b) new methodologies for producing “movies” of the molecular motion which occurs in a phase transition or solid-state reaction, and (c) novel approaches to the understanding of twinning phenomena in crystals. All the topics briefly outlined here are illustrated in the selected publications.
- Use of Topotactic Phase Transformations to Obtain Solutions of the Crystal Structures of Highly Disordered Materials,” Lorson, L. C.; Tai, O.; Foxman, B. M. Cryst. Growth Des. 2017, accepted for publication.
- "An unprecedented case of dodecamorphism: the twelfth polymorph of aripiprazole formed by seeding with its active metabolite," Zeidan, T. A. ; Trotta, J. T.; Tilak, P. A.; Oliveira, M. A.; Chiarella, R. A.; Foxman, B. M.; Almarsson, Ö.; Hickey, M. B. CrystEngComm 2016, 18, 1486-1488 ; http://dx.doi.org/10.1039/C5CE02467F.
- "Experimental Establishment of Mother-Daughter Orientation Relationships and Twinning Effects in Phase Transitions : A Great Legacy from Jack Gougoutas and Peggy Etter," Posner, S. R.; Lorson, L. C.; Gell, A. R.; Foxman, B. M. Cryst. Growth Des. 2015, 15, 3407–3416; http://dx.doi.org/10.1021/acs.cgd.5b00487.
- "Fitting the Pieces of the Puzzle: The Delta Bond," Falvello, L. R.; Foxman, B. M.; Murillo, C. A. Inorg. Chem. 2014, 53, 9441−9456; http://dx.doi.org/10.1021/ic500119h.
- "Stereospecific solid-state cyclodimerization of bis(trans-2-butenoato)calcium and triaquabis(trans-2-butenoato)magnesium," Hickey, M. B.; Schlam, R. F.; Guo, C.; Cho, T. H.; Snider, B. B.; Foxman, B. M. CrystEngComm 2011, 13, 3146-3155; http://dx.doi.org/10.1039/C0CE00535E.
- "Chemo- and stereospecific solid-state dimerization of lithium trans-2-butenoate and lithium trans-2-butenoate formamide solvate," Shang, W.; Hickey, M. B.; Enkelmann, V.; Snider, B. B.; Foxman, B. M. CrystEngComm 2011, 13, 4339-4350; http://dx.doi.org/10.1039/C0CE00810A.
- "Celecoxib sodium salt: engineering crystal forms for performance," Remenar, J. F.; Tawa, M. D.; Peterson, M. L.; Almarsson, Ö. Hickey, M. B.; Foxman, B. M. CrystEngComm 2011, 13, 1081-1089; http://dx.doi.org/10.1039/C0CE00475H.