Combining a Titanium–Organic Cage and a Hydrogen‐Bonded Organic Cage for Highly Effective Third‐Order Nonlinear Optics
Yan‐Ping He, Guang‐Hui Chen, De‐Jing Li, Qiaohong Li, Lei Zhang, Jian Zhang
Abstract
Abstract Many metal–organic cages (MOCs) and a few hydrogen‐bonded organic cages (HOCs) have been investigated, but little is reported about cooperative self‐assembly of MOCs and HOCs. Herein, we describe an unprecedented MOC&HOC co‐crystal composed of tetrahedral Ti 4 L 6 (L=embonate) cages and in‐situ‐generated [(NH 3 ) 4 (TIPA) 4 ] (TIPA=tris(4‐(1 H ‐1,2,4‐triazol‐1‐yl)phenyl)amine) cages. Chiral transfer is observed from the enantiopure Ti 4 L 6 cage to enantiopure [(NH 3 ) 4 (TIPA) 4 ] cage. Two homochiral supramolecular frameworks with opposite handedness ( PTC‐235(Δ) and PTC‐235(Λ) ) are formed. Such MOC&HOC co‐crystal features high stability in water and other solvents, affording single‐crystal‐to‐single‐crystal transformation to trap CH 3 CN molecules and identify disordered NH 4 + cations. A tablet pressing method is developed to test the third‐order nonlinear optical property of KBr‐based PTC‐235 thin film. Such a thin film exhibits an excellent optical limiting effect.