Nano CuO Catalyzed Cross Dehydrogenative Coupling (CDC) of Aldehydes to Anhydrides

Abstract

An elegant synthesis of carboxylic acid anhydrides has been developed directly from arylaldehydes using CuO nanoparticles as the catalyst and tert‐butyl hydroperoxide (TBHP) as the oxidant. During anhydride formation the reaction proceeds through a double sp2 C–H functionalization of aldehydes to generate two consecutive C–O bonds.

Cu-MOF: an efficient heterogeneous catalyst for the synthesis of symmetric anhydrides via the C–H bond activation of aldehydes

“…The results showed a high catalyst proficiency in C–H bond activation and the synthesis of anhydrides. Patel et al 32 have reported that aldehydes with electron-withdrawing groups such as NO 2 in para or ortho positions in the presence of CuO nanoparticles resulted in no product being formed, while in the present work aldehydes with electron-withdrawing groups led to the corresponding anhydrides in relatively good yields. On the other hand, aldehydes with electron-donating groups such as vaniline, 4-methoxy benzaldehyde and 4-hydroxy benzaldehyde were converted to anhydrides with good to excellent yields.…”

“…Recycled Cu 2 (BDC) 2 DABCO aer 5 runs maintained its crystallinity based on PXRD (Fig. 3), but a slight degradation of the structure and hydrolysis reaction 44,45 could possibly justify the presence of the peaks at higher values of 2q (30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40), which probably indicates the presence of Cu(OH) 2 or CuO, 46 which are direct products of this reaction. In fact, under TBHP (70%) Scheme 3 The proposed mechanism for the synthesis of symmetric carboxylic anhydrides via C-H activation.…”

“…[27][28][29] A new approach involves the self-coupling of aldehydes in the presence of transition metal catalysts such as copper. [30][31][32] A major drawback related to earlier methodologies is homogeneous systems and as a result, the isolation of catalysts and work-up are difficult and time consuming. Therefore, the development of new heterogeneous systems for the formation of C-O bonds through C-H bond activation remains a great goal.…”

Ultrafine Copper Oxide Particles Dispersed on Nitrogen‐Doped Hollow Carbon Nanospheres for Oxidative Esterification of Biomass‐Derived 5‐Hydroxymethylfurfural

“…Taking into consideration the outcome of control experimentations and previous reports, [51,53,60] a plausible mechanism is presented (Scheme 2). The reaction begins with generation of a tert-butoxyl or tert-butylperoxyl radicals from TBHP in the presence of CuO/NÀ CÀ HNSs (Step I, Scheme 2).…”

The Rich Legacy and Bright Future of Transition‐Metal Catalyzed Peroxide Based Radical Reactions

“…[40] In 2015, our group employed a nano CuO/TBHP combination for an inter-and intra-molecular double aldehydic CÀ H functionalization leading to the synthesis of symmetrical anhydrides (42) (Scheme 41). [41] Scheme 38. A plausible mechanism for synthesis of 2-aryl-2H-benzotriazoles.…”