One‐Pot Synthesis of Heteroaryl and Diheteroaryl Ketones through Palladium‐Catalyzed 1,2‐Addition and Oxidation

Abstract

A synthetic method was developed for the preparation of heteroaryl and diheteroaryl ketones from aldehydes and organoboronic acids through a palladium‐catalyzed 1,2‐addition and oxidation that uses an aryl iodide as the oxidant. This one‐pot process shows high tolerance for a broad range of heterocyclic substrates by using 1.0–3.0 mol‐% of the catalyst that is formed from allylpalladium chloride dimer and a thioether‐imidazolinium chloride. In addition to fine‐tuning the catalytic system, the use of a sterically hindered aryl iodide that has a substituent at the ortho position, such as 2‐iodotoluene, is important to obtain the desired ketones with heterocyclic moieties in good to excellent yields.

Triphenylphosphinopalladium(II) complexes with ONO‐donor ligands: syntheses, structures and catalytic applications in CC cross‐coupling reactions

“…Though some palladium‐catalysed coupling reactions of arylboronic acids with aromatic aldehydes for the synthesis of diaryl ketones have been reported, a direct comparison of 1 , 2 , 3 with the catalyst systems reported earlier is difficult due to the differences in the reaction conditions such as solvent, base, temperature, reaction time and catalyst loading. However, in terms of the obtained yields, the efficiencies of the present palladium(II) complexes are comparable or slightly superior to those reported in the literature.…”

“…Examples for such palladium‐catalysed coupling reactions of arylboronic acids with aromatic aldehydes for the synthesis of diaryl ketones are very few. To the best of our knowledge, there have been only three reports so far . A one‐pot palladium‐catalysed coupling reaction of aryl aldehydes and organoboronic acids in the presence of P(1‐nap) 3 and Cs 2 CO 3 in toluene under aerobic conditions provided diaryl ketones in moderate to excellent yields .…”

“…A mild but efficient route for the preparation of 2‐hydroxybenzophenone derivatives in high yields is reported to be the palladium‐catalysed coupling of 2‐hydroxyaryl aldehydes with arylboronic acids in O 2 atmosphere using NaHCO 3 as base and CuCl 2 as additive . Preparation of diaryl ketones from aromatic aldehydes and organoboronic acids has been also achieved via palladium‐catalysed 1,2‐addition and oxidation by aryl iodides . The advantages of the palladium‐catalysed coupling reactions between aryl aldehydes and arylboronic acids include the easy availability of aldehydes and arylboronic acids, their stability in air and moisture and high functional group tolerance.…”

An efficient 3-acylquinoline synthesis from acetophenones and anthranilviaC(sp3)–H bond activation mediated by Selectfluor

“…3-Acylquinolines have been reported to possess herbicidal activity 46 as well as antihypertensive activity. 47 Some efficient methods for the preparation of 3-acylquinolines have been developed, such as Pd-catalyzed carbonylative Suzuki crosscoupling reactions of arylboronic acid with 3-iodoquinoline, 48 Pd-catalyzed coupling of aldehydes and 3-bromoquinoline 49 or arylboronic acid and 3-quinolinecarbaldehyde, 50 Fe-catalyzed cascade Michael addition/cyclization of o-aminoaryl aldehydes/ketones/alcohols with ynones, 45 and domino reactions between N,N-dimethyl enaminones and anilines. 41 In addition, dehydrogenation of saturated carbonyl compounds to afford a,b-unsaturated carbonyl derivatives has been found to be compatible with other organic transformations, leading to efficient one-pot protocols for the synthesis of functionalized molecules.…”

Copper-catalyzed one-pot domino reactions via C–H bond activation: synthesis of 3-aroylquinolines from 2-aminobenzylalcohols and propiophenones under metal–organic framework catalysis

“… 7 Kuriyama et al demonstrated a one-pot synthesis of 3-acylquinolines through palladium-catalyzed 1,2-addition and subsequent oxidation. 8 Luo et al synthesized 4-substituted 3-aroylquinolines by utilizing ZnCl 2 -catalyzed Friedländer-type reaction of o -aminoaryl ketones with enaminones. 9 Wan et al developed a protocol to obtain 3-acylquinolines from TfOH-catalyzed domino reactions between N , N -dimethyl enaminones and anilines.…”