title: Coherently aligned porphyrin-appended polynorbornenes.
abstract: Six different kinds of coherently aligned porphyrin-appended polynorbornenes derived from 5,6-endo-fused N-arylpyrrolidenonorbornenes have been synthesized. Pi-pi interactions between the pendant groups are essential for dictating the photophysical properties of the polymers and the mechanism for the stereoselective formation of polymers. Splitting of the Soret band of polymers 2a-c, which have alkyl-substituted porphyrin pendant groups, suggests strong exciton coupling between chromophores. No splitting of the Soret band is observed for polymers 2d-f, which have tetraaryl substituents on the porphyrin moiety. Significant fluorescence quenching is found in polymers 2a-e, whereas only slightly reduced quantum yield is observed for 2f. Time-resolved fluorescence measurements also indicate a similar trend. The AFM image of 2d on graphite shows aggregation to form a two-dimensional, ordered pattern.
authors.affiliation: Department of Chemistry, National Taiwan University, Taipei, 106, Taiwan.
authors.forename: Hsian-Wen
authors.initials: HW
authors.lastname: Wang
authors.forename: Zhi-Chang
authors.initials: ZC
authors.lastname: Liu
authors.forename: Chih-Hsien
authors.initials: CH
authors.lastname: Chen
authors.forename: Tsong-Shin
authors.initials: TS
authors.lastname: Lim
authors.forename: Wunshain
authors.initials: W
authors.lastname: Fann
authors.forename: Chih-Gang
authors.initials: CG
authors.lastname: Chao
authors.forename: Jian-Yuan
authors.initials: JY
authors.lastname: Yu
authors.forename: Shern-Long
authors.initials: SL
authors.lastname: Lee
authors.forename: Chun-hsien
authors.initials: CH
authors.lastname: Chen
authors.forename: Shou-Ling
authors.initials: SL
authors.lastname: Huang
authors.forename: Tien-Yau
authors.initials: TY
authors.lastname: Luh
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D010777:Photochemistry; D010969:Plastics / Q000138:chemical synthesis* / Q000737:chemistry; D011166:Porphyrins / Q000138:chemical synthesis* / Q000737:chemistry; D013329:Structure-Activity Relationship
chemical_list: D010969:Plastics; D011166:Porphyrins; C071464:polynorbornen