Iridium complex-linked porous organic polymers for recyclable, broad-scope photocatalysis of organic transformations

Abstract

Iridium-complex-incorporated porous organic polymers have been prepared to realize the photocatalysis of four organic transformations with previously unattainable recyclability.

Highly Efficient and Recyclable Porous Organic Polymer Supported Iridium Catalysts for Dehydrogenation and Borrowing Hydrogen Reactions in Water

“…Three major peaks were seen in the C 1s spectrum, which are belonged to C−C, C=C, C−H (284.8 eV), C−N (285.8 eV) and C−S (287.2 eV). Iridium 4 f region (Figure 3c) shows two distinct peaks: Ir 4f 5/2 peak at 64.8 eV and Ir 4f 7/2 peak at 61.9 eV, which indicated the Ir(III) oxidation state of iridium element [11] . The N 1s spectrum (Figure 3d) showed two peaks, which are attributed to C−N (398.7 eV), C=N (400.3 eV).…”

Recyclable, Immobilized Transition‐Metal Photocatalysts

“…Li et al developed a convenient strategy for the preparation of iridium(III)-complex-connected porous organic polymers. [42] The synthesis of two highly stable [Ir(ppy) 2 (d t bbpy)] + (ppy: phenylpyridine, d t bbpy: 4,4'di(tert-butyl)-2,2'-bipyridine)-linked porous organic polymers, IrÀ POP-1 and IrÀ POP-2, from Pd-catalyzed coupling reactions of a tetrakisphenyl-methane borate and two [Ir(ppy) 2 (d t bbpy)] + -derived bromides (Figure 21).…”

Highly efficient heterogeneous V2O5@TiO2 catalyzed the rapid transformation of boronic acids to phenols

“…Amongst these, the ipso ‐hydroxylation of boronic acid emerges as the most conventional route for installing the hydroxyl group. In this regard, several methods were reported for the synthesis of phenols which utilized metal catalysts (Pd, [5] Ru, [6] Au, [7] Ag, [8] In, [9] Zn, [10] Cu [11] ), photocatalysts (Ru, [12] Ir, [13] Zn, [14] COF, [15] QDs [16] POF [17] ), electrochemical [18] and in metal‐free conditions (H 2 O 2 , [19] TBHP, [20] m ‐CPBA, [21] oxone, [22] N ‐oxide, [23] peroxodisulfate [24] ) (Figure 1). Previously, Olah and co‐workers reported hydroxylation of boronic acid using hydrogen peroxide and water systems.…”

“…Several other transition metal‐catalyzed reactions were also reported, such as palladium‐chitosan‐CNT core‐shell nanohybrid‐H 2 O 2 system, [5] Ru@imine‐nanoSiO 2 , [6] N ‐doped‐C‐encapsulated ultrafine In 2 O 3 nanoparticles, [9] and K‐10 supported silver nanoparticles‐H 2 O 2 system [8] . Apart from this, photoredox catalytic systems were also explored for the synthesis of phenols using Ru(bpy) 3 , [12] [Ir(OMe)(COD)] 2 , [13] and other organic photocatalysts (COF, QDs, POF). However, most of these photocatalysts utilized noble transition metal and a tedious preparation process.…”