Zn(II)porphyrin Helical Arrays: A Strategy to Overcome Conformational Heterogeneity by Host-Guest Chemistry

Bulletin of the Korean chemical society

Shanmugam Easwaramoorthi¹  Zin Seok Yoon¹  Dongho Kim¹ 

关键词: Zn(II)porphyrin arrays;    Conformational heterogeneity;    Two-photon absorption;    Host-guest binding;    Fluorescence quantum yield;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

Conformational heterogeneity of directly linked multiporphyrin arrays with larger molecular length retards their utilities in practical applications such as two-photon absorption and molecular photonic wire. In this regard, here we adopted a way to overcome the conformational heterogeneity through hydrogen bonding by selective binding of meso aryl substituents of porphyrins (host) with urea (guest) to form helical structure. Using steady-state and time-resolved spectroscopy, we observed the enhanced fluorescence quantum yield by ~1.8 to 2.4 times, enhanced anisotropy values and the disappearance of fast fluorescence decay component in the host-guest helical forms. In addition, the enhanced nonlinear optical responses of helical arrays infer the extended inter-porphyrin electronic coupling due to a significant change in dihedral angle between the neighboring porphyrin moieties. The current host-guest strategy will provide a guideline to improve the structural homogeneity of the photonic wire.

【 授权许可】

Unknown