title: Geometry and temperature dependence of meso-aryl rotation in strained metalloporphyrins: adjustable turnstile Molecules.
abstract: The rotation of meso-aryl groups in porphyrins depends on the degree of macrocyclic distortion and is also influenced by the surrounding temperature. Dynamic NMR methods and crystal structures of series of nonplanar metalloporphyrins reveal that macrocyclic distortion lowers the rotational barrier by weakening the nonbinding interactions of neighboring groups, while increased temperature allows the rotational barrier to be overcome more readily. Two empirical methods are developed to acquire the rotational barrier. This type of strained molecule can act as an adjustable molecular turnstile through adjusting the degree of macrocyclic distortion and changing the surrounding temperature.
authors.affiliation: School of Chemistry and Chemical Engineering, Key Laboratory of Theoretical Chemistry and Molecular Simulation of Ministry of Education, and Hunan Provincial University Key Laboratory of QSAR/QSPR, Hunan University of Science and Technology , Xiangtan 411201, China.
authors.forename: Zaichun
authors.initials: Z
authors.lastname: Zhou
authors.forename: Xi
authors.initials: X
authors.lastname: Zhang
authors.forename: Qiuhua
authors.initials: Q
authors.lastname: Liu
authors.forename: Ziqiang
authors.initials: Z
authors.lastname: Yan
authors.forename: Chengjin
authors.initials: C
authors.lastname: Lv
authors.forename: Ge
authors.initials: G
authors.lastname: Long