5747-23-9Relevant articles and documents
Lewis acid-catalysed formation of two-dimensional phthalocyanine covalent organic frameworks
Spitler, Eric L.,Dichtel, William R.
, p. 672 - 677 (2010)
Covalent organic frameworks (COFs) offer a new strategy for assembling organic semiconductors into robust networks with atomic precision and long-range order. General methods for COF synthesis will allow complex building blocks to be incorporated into these emerging materials. Here we report a new Lewis acid-catalysed protocol to form boronate esters directly from protected catechols and arylboronic acids. This transformation also provides crystalline boronate ester-linked COFs from protected polyfunctional catechols and bis(boronic acids). Using this method, we prepared a new COF that features a square lattice composed of phthalocyanine macrocycles joined by phenylene bis(boronic acid) linkers. The phthalocyanines stack in an eclipsed fashion within the COF to form 2.3 n pores that run parallel to the stacked chromophores. The material's broad absorbance over the solar spectrum, potential for efficient charge transport through the stacked phthalocyanines, good thermal stability and the modular nature of COF synthesis, show strong promise for applications in organic photovoltaic devices.
Activation of Aryl Carboxylic Acids by Diboron Reagents towards Nickel-Catalyzed Direct Decarbonylative Borylation
Deng, Xi,Guo, Jiandong,Su, Weiping,Wang, Xiaotai,Zhang, Xiaofeng
supporting information, p. 24510 - 24518 (2021/08/12)
The Ni-catalyzed decarbonylative borylation of (hetero)aryl carboxylic acids with B2cat2 has been achieved without recourse to any additives. This Ni-catalyzed method exhibits a broad substrate scope covering poorly reactive non-ortho-substituted (hetero)aryl carboxylic acids, and tolerates diverse functional groups including some of the groups active to Ni0 catalysts. The key to achieve this decarbonylative borylation reaction is the choice of B2cat2 as a coupling partner that not only acts as a borylating reagent, but also chemoselectively activates aryl carboxylic acids towards oxidative addition of their C(acyl)?O bond to Ni0 catalyst via the formation of acyloxyboron compounds. A combination of experimental and computational studies reveals a detailed plausible mechanism for this reaction system, which involves a hitherto unknown concerted decarbonylation and reductive elimination step that generates the aryl boronic ester product. This mode of boron-promoted carboxylic acid activation is also applicable to other types of reactions.
Electronic Spectroscopy of 2-Phenyl-1,3,2-benzodioxaborole and Its Derivatives: Important Building Blocks of Covalent Organic Frameworks
Jimenez-Hoyos, Carlos A.,Knee, Joseph L.,Northrop, Brian H.,Ryan, Roberta P.,Savino, Cara
, p. 529 - 537 (2020/02/25)
Aryl boronate esters, such as 2-phenyl-1,3,2-benzodioxaborole (1), are important components in the formation of a variety of covalent organic frameworks. The addition of substituents on the aromatic rings of aryl boronate esters has the potential to modif