Controlled Linker Dependence of Solution-and Solid-State Emission of Vaulted trans-Bis(salicylaldiminato)-platinum(II) Complexes with Amino Functionalities

摘要

The synthesis, structures, and emission properties of vaulted trans-bis(salicylaldiminato)platinum(II) complexes 1 with diethylamino functionalities are described and compared with the non-substituted analogues. The amino substitution provides an improvement of the linker dependence both for the color change of the trans-bis(salicylaldiminato)platinum(II) platform in the glass state and for the acid-induced emission enhancement in the solution state. The linker dependence of the crystalline-state emission intensity changes with the amino functionality, which leads to intense emission of the vaulted crystals with low structural dependence. Single-crystal X-ray diffraction studies and DFT calculations revealed that the unique photophysical properties arising from the amino functionality are attributable to enhanced planarity and self-constraint of the coordination platform, which is due to their strong contribution to d-π conjugation and intermolecular hydrogen bonding.