Suzuki-Miyaura cross-coupling of benzylic carbonates with arylboronic acids

The cross-coupling of benzylic carbonates with arylboronic acids gave the corresponding diarylmethanes in high yields by use of the palladium catalyst generated in situ from [Pd(eta(3)-C(3)H(5))Cl](2) and 1,5-bis(diphenylphosphino)pentane (DPPPent). The Suzuki-Miyaura reaction using DPPPent-palladium catalyst is applicable to syntheses of a broad range of functionalized diarylmethanes. [reaction: see text]     

Nickel-catalyzed cross-coupling of aryl phosphates with arylboronic acids

The Suzuki-Miyaura cross-coupling of aryl phosphates using Ni(PCy(3))(2)Cl(2) as an inexpensive, bench-stable catalyst is described. Broad substrate scope and high efficiency are demonstrated by the syntheses of more than 40 biaryls and by constructing complex organic molecules. The poor reactivity of aryl phosphates relative to aryl halides is successfully employed to construct polyarenes by selective cross-coupling using Pd and Ni catalysts.     

Azidosubstituted arylboronic acids: synthesis and Suzuki-Miyaura cross-coupling reactions

Arylboronic acids having a remote azido group were prepared from the corresponding azidosubstituted aryl bromides via lithiation and treatment with trialkyl borates. Preparative yields were achieved when the starting aryl bromides possessed ortho-alkoxy groups, which would stabilize the intermediate aryllithium species. Conventional Suzuki cross-coupling of the arylboronic acids proceeded generally well with retention of azido group; however, sometimes azidomethyl fragment underwent oxidative transformation into a nitrile.     

Suzuki-Miyaura cross-coupling of heteroaryl halides and arylboronic acids in continuous flow

General continuous-flow conditions for the Suzuki-Miyaura cross-coupling of heteroaryl halides and (hetero)arylboronic acids have been developed. A wide range of heterobiaryl products is obtained in excellent yields (20 examples) employing low catalyst loadings (0.05-1.5 mol % Pd).     

Synthesis of diarylmethane derivatives from Pd-catalyzed cross-coupling reactions of benzylic halides with arylboronic acids

A simple catalyst precursor prepared in situ from palladium acetate and triphenylphosphine shows high activity for the Suzuki cross-coupling reaction of benzylic bromides and chlorides with aryl boronic acids. The reaction can be carried out at low catalyst loading (0.002-1 mol%) and under mild conditions (room temperature to 80 °C) furnishing diarylmethane derivatives in high yields (86-99%).     

Base-free Pd-MOF catalyzed the Suzuki-Miyaura cross-coupling reaction of arenediazonium tetrafluoroborate salts with arylboronic acids

A convenient and environmental benign synthesis of biaryls has been demonstrated by a straightforward reaction catalyzed by the palladium-containing metal-organic framework (Pd-MOF) [Pd (2-pymo)₂]_n (2-pymo = 2-pyrimidinolate). A series of functionalized biaryl derivatives have been synthesized in good to excellent yields by the Suzuki-miyaura cross-couplings of sustainable arenediazonium salts with a variety of arylboronic acids and the reactions were catalyzed by the Pd-MOF using methanol as a benign solvent. Those base- and additive-free catalytic reactions proceeded smoothly under non-anhydrous and non-degassed condition. Such transformation avoided high reaction temperature, tolerated many functional groups and presented a wide substrate scope. The catalyst could be recovered by filtration and reused for four successive cycles before collapse of the MOF structure.     

Suzuki cross-coupling of solid-supported chloropyrimidines with arylboronic acids

The utility of the Suzuki cross-coupling to synthesize biaryl compounds is expanded herein to include reactions of resin-supported chloropyrimidines with boronic acids. In particular, an efficient method is described for the synthesis of a library of biaryl compounds from solid-supported chloropyrimidines. The Suzuki reaction was performed in an inert atmosphere using Pd(2)(dba)(3)/P(t-Bu)(3) as catalyst, spray-dried KF as base, and THF as solvent. The reaction was allowed to proceed overnight at 50 degrees C. Upon cleavage with acid, a library of 4-(substituted amino)-6-arylpyrimidines was obtained in moderate yield and high purity.     

Practical and efficient Suzuki-Miyaura cross-coupling of 2-iodocycloenones with arylboronic acids catalyzed by recyclable Pd(0)/C

The first Suzuki-Miyaura cross-coupling of 2-iodocycloenones with arylboronic acids catalyzed by 10% Pd(0)/C is described as an interesting alternative to classical homogeneous conditions. Most of the substrate reacted under mild condition at 25 degrees C under air in aqueous DME. The conditions described tolerate a wide range of iodoenones and boronic acids. Notably, the procedure features inexpensive reagents and solvents with low toxicity rendering the method environmentally benign. Additionally 10% Pd(0)/C could be recovered and efficiently reused at least five times without significant alteration of the yields of the cross-coupled product.     

Palladium-catalyzed cross-coupling reactions of 2-diazonaphthoquinones with arylboronic acids

Palladium-catalyzed cross-coupling reactions of 2-diazonaphthoquinones and arylboronic acids proceeded by the treatment with Pd(OAc)₂ in acetic acid to afford 2-aryl-1-naphthols.     

Cross-coupling of benzylic acetates with arylboronic acids: one-pot transformation of benzylic alcohols to diarylmethanes

Benzylic acetates reacted with arylboronic acids in the presence of a DPEphos-[Pd(eta3-C3H5)Cl]2 catalyst when tert-amyl alcohol was used as a solvent, and the catalytic cross-couplings produced diarylmethanes in high yields (up to 94% isolated yield).     

First Suzuki-Miyaura type cross-coupling of ortho-azidobromobenzene with arylboronic acids and its application to the synthesis of fused aromatic indole-heterocycles

A short synthesis of some fused indole-heterocycles has been achieved via Pd-catalyzed cross-coupling reactions between azido-2-bromobenzene and arylboronic acids and subsequent thermally induced nitrene insertion. Additionally, 4-amino-α-carboline, a versatile intermediate toward grossularine analogs has also been prepared by Suzuki-Miyaura cross-coupling of 4-pivaloylaminopyridine-3-boronic acid with 2-bromoaniline, followed by simple functional group transformations.     

Synthesis of arylketones by ruthenium-catalyzed cross-coupling of aldehydes with arylboronic acids

The first ruthenium-catalyzed cross-coupling of aldehydes with arylboronic acids is reported. Various aliphatic and aromatic aldehydes are transformed to the corresponding arylketones. A total of 31 examples with moderate to excellent yields are presented, together with the results of an initial mechanistic investigation.     

Pd-catalyzed regioselective and stereospecific Suzuki-Miyaura coupling of allylic carbonates with arylboronic acids

The Pd-catalyzed Suzuki-Miyaura coupling reaction of unsymmetric 1,3-disubstituted secondary allylic carbonates with arylboronic acids has been developed in a wet solvent under a base-free system to afford allyl-aryl coupling products in a high level of isolated yields with complete regio- and E/Z-selectivities with good to excellent chemoselectivities. The coupling reaction of optically active allyl carbonates gave allyl-aryl coupling products with excellent enantioselectivities with inversion of the stereochemistry. This coupling method was successfully applied to the synthesis of (S)-naproxen.     

Direct one-pot synthesis of primary 4-amino-2,3-diaryl-quinolines via Suzuki-Miyaura cross-coupling of 2-aryl-4-azido-3-iodoquinolines with arylboronic acids

Palladium-catalyzed Suzuki-Miyaura cross-coupling of 2-aryl-4-azido-3-iodo-quinolines with arylboronic acids afforded the corresponding primary 4-amino-2,3-diarylquinolines in a single-pot operation along with symmetrical biaryls and traces of the 2,3-diaryl-4-azidoquinolines. A plausible mechanism, which implicates palladium hydride species in the reduction of the incipient 2,3-diaryl-4-azidoquinolines to afford the 4-amino-2,3-diarylquinolines is proposed.     

Synthesis of functionalized diarylmethanes via a copper-catalyzed cross-coupling of arylmagnesium reagents with benzylic phosphates

A combination of copper chloride, triethyl phosphite, and tetrabutylammonium iodide is a very efficient catalytic system for the synthesis of polyfunctionalized diarylmethanes, using the cross-coupling reaction of arylmagnesium halides with benzylic phosphates. The antibiotic Trimethoprim has been prepared using this Cu(I)-catalyzed cross-coupling in 52% overall yield (four steps).     

Facile Pd-catalyzed cross-coupling of 2'-deoxyguanosine O6-arylsulfonates with arylboronic acids

[reaction: see text]. The O6-(2-mesitylenesulfonyl) derivative of 2'-deoxyguanosine undergoes a facile palladium-mediated C-C cross-coupling with arylboronic acids. Demonstrating the general applicability of this method, the synthesis of a previously undescribed class of 2-amino-6-arylpurine 2'-deoxynucleosides has been accomplished. The study also describes an evaluation of the O6-(2,4,6-triisopropylphenylsulfonyl) and the O6-(4-toluenesulfonyl) derivatives for the cross-coupling.     

A base-free, one-pot diazotization/cross-coupling of anilines with arylboronic acids

Pd-catalyzed one-pot diazotization/cross-coupling is realized for the synthesis of biaryls directly from anilines and arylboronic acids.     

Room-temperature Ni0-catalyzed cross-coupling reactions of aryl arenesulfonates with arylboronic acids

Room-temperature Ni(0)-catalyzed cross-coupling reactions of aryl arenesulfonates with arylboronic acids are described. The Ni(0) catalyst, derived from Ni(COD)2 and PCy3, proved to be a general one for the Suzuki-Miyaura cross-coupling of a variety of aryl arenesulfonates. The mild reaction condition, the readily availability of the catalyst, and excellent coupling yields make aryl arenesulfonates potentially useful substrates in organic synthesis.     

Palladacycle-catalyzed cross-coupling reactions of arylboronic acids with carboxylic anhydrides or acyl chlorides

The triphenylphosphine–cyclopalladated ferrocenylimine (Cat. 2) exhibited highly catalytic activity for the both of arylboronic acids with carboxylic anhydrides and acyl chlorides with low catalyst loading (0.5 mol %). The reactions were unaffected by the presence of electron-releasing and electron-withdrawing substituents in both the arylboronic acids and carboxylic derivatives. Up to 98% yield was obtained for 32 examples. However, they were limited for arylboronic acid with strong electron-withdrawing groups. It is noting that catalyst 2 can be reused for eight times without losing its catalytic activity.