Metal-free one-pot oxidative conversion of benzylic alcohols and benzylic halides into aromatic amides with molecular iodine in aq ammonia, and hydrogen peroxide

Acceptorless dehydrogenative synthesis of primary amides from alcohols and ammonia

The highly desirable synthesis of the widely-used primary amides directly from alcohols and ammonia via acceptorless dehydrogenative coupling represents a clean, atom-economical, sustainable process. Nevertheless, such a reaction has not been previously reported, and the existing catalytic systems instead generate other N-containing products, e.g., amines, imines and nitriles. Herein, we demonstrate an efficient and selective ruthenium-catalyzed synthesis of primary amides from alcohols and ammonia gas, accompanied by H2 liberation. Various aliphatic and aromatic primary amides were synthesized in high yields, with no observable N-containing byproducts. The selectivity of this system toward primary amide formation is rationalized through density functional theory (DFT) calculations, which show that dehydrogenation of the hemiaminal intermediate into primary amide is energetically favored over its dehydration into imine.

Fluorinated solvent-assisted photocatalytic aerobic oxidative amidation of alcohols via visible-light-mediated HKUST-1/Cs-POMoW catalysis

Successful synthesis and characterization of HKUST-1/Cs-POMoW binary composite, and application in the photocatalytic aerobic oxidative amidation reaction of alcohols under light illuminating in the visible region.

A two-step telescoped continuous flow switchable process leading to nitriles, diaziridine or hydrazine derivatives

Primary and benzylic alcohols were converted into nitriles on a continuous flow MJOD reactor platform or with a batch protocol. The two steps process involves TEMPO as the precatalyst with DIH and DCH as the terminal oxidants, respectively.

Systematic Structure-Activity Relationship (SAR) Exploration of Diarylmethane Backbone and Discovery of A Highly Potent Novel Uric Acid Transporter 1 (URAT1) Inhibitor

In order to systematically explore and better understand the structure-activity relationship (SAR) of a diarylmethane backbone in the design of potent uric acid transporter 1 (URAT1) inhibitors, 33 compounds (1a-1x and 1ha-1hi) were designed and synthesized, and their in vitro URAT1 inhibitory activities (IC₅₀) were determined. The three-round systematic SAR exploration led to the discovery of a highly potent novel URAT1 inhibitor, 1h, which was 200- and 8-fold more potent than parent lesinurad and benzbromarone, respectively (IC₅₀ = 0.035 μM against human URAT1 for 1h vs. 7.18 μM and 0.28 μM for lesinurad and benzbromarone, respectively). Compound 1h is the most potent URAT1 inhibitor discovered in our laboratories so far and also comparable to the most potent ones currently under development in clinical trials. The present study demonstrates that the diarylmethane backbone represents a very promising molecular scaffold for the design of potent URAT1 inhibitors.

Copper-amino group complexes supported on silica-coated magnetite nanoparticles: efficient catalyst for oxidative amidation of methyl arenes

Magnetite nanoparticles coated with mesoporous silica, Fe₃O₄@SiO₂, were prepared.

Copper (II)-catalysed direct conversion of aldehydes into nitriles in acetonitrile

A mild one-pot method for the direct conversion of aryl, heteroaryl and alkyl aldehydes into nitriles was achieved by forming the corresponding oximes in situ with NH2OH and allowing them to react with CuO and acetonitrile. Yields of the 13 nitriles prepared were moderate to very good (62–91%).

Cu-catalyzed aerobic oxidative C–CN bond cleavage of benzyl cyanide for the synthesis of primary amides

Cu-catalyzed oxidative amidation of benzyl cyanide for primary amides is successfully developed. Using readily available NH₄Cl and Cu/O₂ catalytic oxidation system offers new opportunities for C–CN bond cleavage and primary amides bond formation.

Pyridoxine-derived bicyclic amido-, ureido-, and carbamato-pyridinols: synthesis and antiangiogenic activities

We recently developed an efficient and practical synthesis for a novel series of pyridoxine-derived 6-amido-2,4,5-trimethylpyridin-3-ols and found that this novel scaffold has outstanding activity to inhibit angiogenesis measured by the quantitative chick embryo chorioallantoic membrane (CAM) assay. As an effort to extend the scope of the amidopyridinol scaffold, we here report the synthesis and antiangiogenic activities of a series of bicyclic versions of the amidopyridinol including five- and six-membered cyclic amide-, cyclic urea-, and cyclic carbamate-fused pyridinols. The six membered bicyclic derivatives were prepared by the reported procedures, and the five-membered ring-fused ones were synthesized by new synthetic methods developed in this study. CAM assays showed that both six- and five-membered lactam-fused pyridinols have activities comparable to sunitinib malate, the positive control, in inhibition of vascular endothelial growth factor-induced angiogenesis. On the other hand, the urea and the carbamate derivatives showed modest to moderate antiangiogenic activities. In summary, some bicyclic aminopyridinols can provide a good platform for structural exploitation in future medicinal chemistry work.

Palladium on manganese ferrite: an efficient catalyst for one pot synthesis of primary amides from iodobenzene

Amidation of aryl iodide in one pot is reported using Pd–MnFe₂O₄ as a catalyst.

Hypervalent iodine-catalyzed oxidative amidation of methylarenes

Hypervalent iodine-catalyzed oxidative amidation of methylarenes to the corresponding amides by using an oxidant (tert-butyl hydroperoxide, 70% aqueous solution) is discussed.