Surface‐Confined Dynamic Covalent System Driven by Olefin Metathesis

Abstract

Understanding how the constitutional dynamics of a dynamic combinatorial library (DCL) adapts to surfaces (compared to bulk solution) is of fundamental importance to the design of adaptive materials. Submolecular resolved scanning tunneling microscopy (STM) can provide detailed insights into olefin metathesis at the interface. Analysis of the distribution of products has revealed the important role of environmental pressure, reaction temperature, and substituent effects in surface-confined olefin metathesis. We also report an unprecedented preferred deposition and assembly of linear polymers, and some specific oligomers, on the surface that are hard to obtain otherwise.

Acid‐Assisted Direct Olefin Metathesis of Unprotected Carbohydrates in Water

“…[4][5][6][7][8][9] Furthermore, the dynamic nature of the reaction is an attractive feature that has been exploited to generate, for example, dynamic systems, complexa rchitectures, and self-healing materials. [10][11][12][13][14][15][16][17][18][19][20] Ever since the introductiono ft he olefin metathesis reaction, much efforth as been invested in improving the catalysts. This has resulted in the appearance of commercially available and bench-stable catalysts, [21][22][23][24][25] Z-selective catalysts, [26][27][28] and highly active catalysts for ethenolysis.…”

Interfacial Synthesis of Conjugated Crystalline 2D Fluorescent Polymer Film Containing Aggregation‐Induced Emission Unit

“…2D materials have attracted extensive attention in recent years for their potential applications arising from the unique thin film structures . However, precise synthesis of highly ordered organic 2D structure is a still challenging task due to synthetic difficulties in forming covalent bonded 2D crystals.…”

Separation of Arylenevinylene Macrocycles with a Surface‐Confined Two‐Dimensional Covalent Organic Framework

“…[5][6][7][8][9] Nevertheless,c ovalently linked two-dimensional (2D) nanoporous networks confined on as urface,k nown as surface covalent organic frameworks (surface COFs), [10] are more robust than supramolecular networks.S urface COFs,h aving nanometersized cavities within ap eriodic pattern, are of significant importance and great interest to act as host networks and nanofilters,and can lead to applications in various domains of nanotechnology. [20][21][22] Avariety of surface-mediated reactions have been explored, involving Ullmann radical coupling, [17,[23][24][25][26] Glaser coupling, [27] acylation reaction, [28,29] self-condensation of boronic acids, [30,31] boronate esterification, [15,32,33] Schiff-base reactions, [21,22,[34][35][36][37][38][39][40] and olefin metathesis, [41] etc. [20][21][22] Avariety of surface-mediated reactions have been explored, involving Ullmann radical coupling, [17,[23][24][25][26] Glaser coupling, [27] acylation reaction, [28,29] self-condensat...…”

“…[4a, 11-14] In recent years,the synthesis of surface COFs has received much attention and has been successfully performed both under ultra-high vacuum (UHV) [15][16][17][18][19] and ambient conditions. [20][21][22] Avariety of surface-mediated reactions have been explored, involving Ullmann radical coupling, [17,[23][24][25][26] Glaser coupling, [27] acylation reaction, [28,29] self-condensation of boronic acids, [30,31] boronate esterification, [15,32,33] Schiff-base reactions, [21,22,[34][35][36][37][38][39][40] and olefin metathesis, [41] etc. Schiff-base reactions and boronic acid condensations are the most studied so far.…”

“…Previously we found that although the AV M2 sample can be purified by column chromatography,s canning tunneling microscopy (STM) still detects as ignificant abundance of linear byproducts on the bare HOPG surface,p ossibly because of preferential adsorption of these linear polymers. [41] We hypothesized that patterning of the HOPG surface with aCOF consisting of pores that can accommodate AV Ms could reverse the adsorption preference through forming hostguest architectures,thus leading to preferential adsorption of AV Ms rather than linear polymers.Ifwecan realize stepwise removal of linear polymers,thus leaving AV Ms bound to the host COF,b ys equential washing with proper solvents,t he purification of AV Ms can be achieved through such onsurface purification.…”