Double-Supported Silica-Metal–Organic Framework Palladium Nanocatalyst for the Aerobic Oxidation of Alcohols under Batch and Continuous Flow Regimes

Abstract

This is the accepted version of a paper published in ACS Catalysis. This paper has been peerreviewed but does not include the final publisher proof-corrections or journal pagination.

Aerobic Homocoupling of Arylboronic Acids Catalyzed by Regenerable Pd(II)@MIL‐88B‐NH2(Cr)

“…Interestingly, the XRPD pattern of the recovered material revealed that the framework did not decompose after five reaction runs (Figure a), despite the previously reported detrimental effect of carbonates on its mesoporous polymorph MIL‐101‐NH 2 . Slight changes were observed in the 2Θ value and relative intensities of the main diffraction peaks; this has been reported previously for this MOF, and ascribed to its flexible nature . On the other hand, the activity of the catalyst was retained only until the second run, when a yield of 70 % of the main product was obtained (Figure b, blue bars).…”

“…Our group has developed several procedures using Pd nanoparticles supported on MIL‐101‐NH 2 (Cr) and MIL‐88B‐NH 2 (Cr). The excellent catalytic activity of the resulting materials has been demonstrated in a wide variety of transformations, including Suzuki‐Miyaura cross‐couplings, C−H activation/halogenations, selective C=C hydrogenations, Heck couplings, different carbonylation reactions and the aerobic oxidation of benzylic alcohols . The catalytic methods we developed using these heterogeneous Pd catalysts were efficient, and in some cases they even surpassed their homogeneous counterparts.…”

“…In this paper, we describe an efficient Pd(II)‐catalyzed heterogeneous protocol for the fast aerobic homocoupling of arylboronic acids. Pd(II)@MIL‐88B‐NH 2 (Cr) was chosen as the catalyst due to its previous good results in terms of activity, stability, and ease of synthesis . This method showed a high substrate tolerance, and gave good product yields at low catalyst/base loadings under very mild reaction conditions.…”

Versatile Heterogeneous Palladium Catalysts for Diverse Carbonylation Reactions under Atmospheric Carbon Monoxide Pressure

“…Our group has gained extensive experience in the development of heterogeneous processes catalyzed by MOF‐supported Pd nanoparticles. Excellent activity together with an important contribution from the solid support were observed in reactions such as C−C cross‐couplings, alcohol oxidation, C−H functionalization, and selective C=C hydrogenation . However, in some cases significant structural differences were observed between the fresh and recycled catalysts.…”

Nanocatalysis in Flow

“…Representation of the synthesis of Pd@MIL-88B-NH 2 @nano-SiO 2 .TEOS = tetraethyl orthosilicate.R eprinted with permission from Ref. [47].Copyright 2015A merican Chemical Society. Figure 6.…”