title: Calix[4]phyrins. Effect of peripheral substituents on conformational mobility and structure within a series of related systems.
abstract: A new, stepwise synthesis of calix[4]phyrins is described. It relies on the condensation of a ketone with pyrrole to form a dipyrromethane containing a quaternary carbon center that is subsequently condensed with an aromatic aldehyde. This methodology, in contrast to the previous rational approach described by this group (involving formation of a trisubstituted dipyrromethane via the condensation of an aldehyde with pyrrole, followed by condensation of this dipyrromethane with acetone), allows for a variety of bulky, ketone-derived substituents to be incorporated into the meso-like positions. The resulting systems, while all containing the same central macrocyclic core, display conformational properties that reflect the nature of these meso-like substituents; these conformational features were independently assessed by X-ray diffraction analysis, NMR spectroscopy, and quantum chemical calculations.
authors.affiliation: Department of Analytical Chemistry and Laboratory of NMR Spectroscopy, Institute of Chemical Technology, Technická 5, 16628 Praha 6, Czech Republic.
authors.forename: Bohumil
authors.initials: B
authors.lastname: Dolenský
authors.forename: Jirí
authors.initials: J
authors.lastname: Kroulík
authors.forename: Vladimír
authors.initials: V
authors.lastname: Král
authors.forename: Jonathan L
authors.initials: JL
authors.lastname: Sessler
authors.forename: Hana
authors.initials: H
authors.lastname: Dvoráková
authors.forename: Petr
authors.initials: P
authors.lastname: Bour
authors.forename: Markéta
authors.initials: M
authors.lastname: Bernátková
authors.forename: Christophe
authors.initials: C
authors.lastname: Bucher
authors.forename: Vincent
authors.initials: V
authors.lastname: Lynch
mesh_terms: D047250:Calixarenes / Q000138:chemical synthesis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008968:Molecular Conformation; D011166:Porphyrins / Q000138:chemical synthesis / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D011166:Porphyrins; D047250:Calixarenes