空間可変型の超分⼦サブナノチューブ −作製後の構造と機能の簡便改変に成功−

2026-05-27 東京科学大学

図1. 超分子チューブの作製後修飾：筒型チューブの配位子修飾による樽型チューブ（左）と金属イオン修飾によるキラルチューブ（右）の作製（修飾箇所を赤で示す）

＜関連情報＞

• https://www.isct.ac.jp/ja/news/akak2c5ijdoa
• https://pubs.acs.org/doi/10.1021/jacs.6c02007

後アセンブリ配位子／金属修飾による多環芳香族サブナノチューブの空洞収縮とキラル化 Cavity Constriction and Chiralization of Polyaromatic Subnanotubes via Post-assembly Ligand/Metal Modification

Shusuke Yamato,Koki Tagai,Yuya Tanaka,Daiki Tauchi,Masashi Hasegawa,and Michito Yoshizawa
Journal of the American Chemical Society  Published: March 26, 2026
DOI:https://doi.org/10.1021/jacs.6c02007

Abstract

Late-stage modification of coordination-driven tubular and cage-like structures is a promising method to tune and alter their cavity functions yet remains difficult owing to the intrinsic instability of metal–ligand bonds against the modification conditions. Here we report polyaromatic tubes with a subnanometer-sized cavity, composed of three metal hinges and three polyaromatic ligands, both of which are modifiable in a post-assembly fashion. The new subnanotube, prepared from PtCl₂ salts and the anthracene-embedded bispyridine ligands, is reversibly converted into a constricted subnanotube by the symmetrical modification of the ligands with O₂. Using an analogous aqueous tube, one molecule of rod-like coumarin dyes is bound by the subnanocavity in water, and their emission properties are largely enhanced (up to 4-fold) through the ligand modification. On the other hand, the asymmetrical modification of the metal hinges with chiral ammonium groups generates a cryptochiral subnanotube while retaining the polyaromatic cavity. The resultant tube also binds the coumarin dye in water to induce its chiroptical properties as strong CD and CPL activities (up to |g_abs| = 2 × 10^–3 and |g_lum| = 3 × 10^–3). Two-directional post-assembly multi-modifications are demonstrated unprecedentedly, using polyaromatic subnanotubes, for the development of multi-functional host–guest systems.