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A highly efficient Suzuki coupling of N‐tosyl aryltriazenes with diarylborinic acids or potassium diaryldifluoroborinates is reported under weak basic conditions in aqueous DME or dioxane, respectively. The shelf‐stable and easy‐to‐stoichiometry diaryldifluoroborinates displayed reactivities comparable to the corresponding diarylborinic acids. Scope and limitations of the protocol have been investigated, showing large electronic and steric effects from aryltriazenes. Utility of potassium diaryldifluoroborinates in the Suzuki coupling with activated aryltriazenes provides a cost‐effective and operationally practical access to biaryls from anilines. [ABSTRACT FROM AUTHOR]

A practical and efficient Suzuki coupling of phenols has been developed by using trans-NiCl(o-Tol)(PCy3)2/2PCy3 as a catalyst in the presence of tosyl fluoride as an activator. The key for the direct use of phenols lies in the compatibility of the nickel catalyst with tosyl fluoride (TsF) and its sulfur(VI) fluoride exchange (SuFEx) with CAr-OH. Water has been found to improve the one-pot process remarkably. The steric and electronic effects and the functional group compatibility of the one-pot Suzuki coupling of phenols appear to be comparable to the conventional one of pre-prepared aryl tosylates. A series of electronically and sterically various biaryls could be obtained in good to excellent yields by using 3–10 mol% loading of the nickel catalyst. The applications of this one-pot procedure in chemoselective derivatization of complex molecules have been demonstrated in 3-phenylation of estradiol and estrone. [ABSTRACT FROM AUTHOR]

Aryltriazenes can hardly take part in productive organic transformations unless stoichiometric Brönsted or Lewis acid activators are used. We report here for the first time a palladium‐catalyzed Suzuki coupling of aryltriazenes activated by a sulfonyl group at N3 atom under the common basic conditions. Benefiting from elimination of stoichiometric acid activators, activated aryltriazenes could efficiently couple with arylboronic acids to afford diaryls in modest to excellent yields by using a simple catalyst at low loading, 0.3 mol% Pd(PPh3)2Cl2. Scope and limitation of the coupling are demonstrated with 26 examples. [ABSTRACT FROM AUTHOR]

A practical approach has been developed for efficient synthesis of unsymmetrical aryl s-triazines via highly selective sequential Suzuki coupling of cyanuric chloride (2,4,6-trichlorotriazine) with aryl or vinyl boronic or diarylborinic acids catalysed by 0.1-0.5 mol% Pd(PPh3)2Cl2 under mild conditions. The second and third Suzuki couplings for unsymmetrically trisubstituted aryl s-triazines could be more practically conducted in one-pot procedure. An electron-withdrawing conjugate group at phenyl ring of arylboronic acids was unexpectedly found to completely block the coupling while steric hindrance from an ortho electron-donating substituent could be overcome. [ABSTRACT FROM AUTHOR]

A highly efficient palladium-catalyzed acylative cross-coupling of carboxylic amides with arylboronic acids has been achieved via synergistic activation of the Cacyl–N bond by independently modifiable activating groups. Coupling of amides features not only good functional group tolerance but also modifiable reactivities to overcome steric hindrance. [ABSTRACT FROM AUTHOR]

An N-heterocyclic carbene and phosphite synergistically enhanced Pd/C catalyst system has been developed for of aryl chlorides and aryl boronic acids from commercially available Pd/C with sterically demanding N, N′-bis(2,6-diisopropylphenyl)imidazolylidene and trimethylphosphite. A remarkable increase in of Pd/C was observed when used along with 1 equiv. N, N′-bis(2,6-diisopropylphenyl)imidazolium chloride and 2 equiv. phosphite with respect to palladium in appropriate solvents that were found to play a crucial role in Pd/C-NHC-P(OR)3-catalyzed . A dramatic ortho-substitution effect of carbonyl and nitrile groups in aryl chlorides was observed and explained by a modified quasi-heterogeneous mechanism. The Pd/C catalyst could be easily recovered from reaction mixtures by simple filtration and only low palladium contamination was detected in the biparyl products. A practical process for the synthesis of 4-biphenylcarbonitrile has therefore been developed using the N-heterocyclic carbene/phosphite-assisted Pd/C-catalyzed . Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A highly efficient acylative cross-coupling of trialkylboranes with activated amides has been effected at room temperature to give the corresponding alkyl ketones in good to excellent yields by using 1,3-bis(2,6-diisopropyl)phenylimidazolylidene and 3-chloropyridine co-supported palladium chloride, the PEPPSI catalyst, in the presence of K2CO3 in methyl tert-butyl ether. The scope and limitations of the protocol were investigated, showing good tolerance of acyl, cyano, and ester functional groups in the amide counterpart while halo group competed via the classical Suzuki coupling. The trialkylboranes generated in situ by hydroboration of olefins with BH3 or 9-BBN performed similarly to those separately prepared, making this protocol more practical. [ABSTRACT FROM AUTHOR]

A new highly efficient palladium-catalyzed acylative cross-coupling of carboxylic amides with arylboronic acids features not only good functional group tolerance but also modifiable reactivities to overcome steric hindrance. [ABSTRACT FROM AUTHOR]

• Sequential olefin hydroboration/palladium-catalyzed alkyl suzuki coupling. • Easy access to ortho n -alkyl benzamides from anthranilic acid derivatives. • Readily available α-olefins as primary alkyl sources. • High primary alkyl selectivity. A denitrogenative alkylation of N -aryl benzotriazinones using readily available α-olefins as alkyl sources via a hydroboration/palladium-catalyzed alkyl Suzuki coupling sequence is reported to afford ortho n -alkyl benzamides in good to excellent yields. Scope and limitations of the sequential hydroboration/Suzuki coupling protocol have been explored, showing large steric effects of both benzotriazinone core and alkylboranes. Only primary alkyl group of trialkylboranes from anti -Markovnikov hydroboration of α-olefins could be effectively coupled, making the protocol highly selective for ortho n -alkyl benzamides. A highly selective hydroboration/palladium-catalyzed alkyl Suzuki coupling sequence is reported for efficient access to ortho n -alkyl secondary N -arylbenzamides from anthranilic acid derived 1,2,3-benzotriazinones under mild conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

An improved acylative cross-coupling of various N -methyl- N -tosyl amides with diarylborinic acids for synthesis of aryl ketones is developed. In most cases, aryl ketones could be obtained in excellent yields by using 1 mol% 2,6-diisopropylphenylimidazolylidene and 3-chloropyridine co-supported palladium chloride as catalyst in the presence of 3 equiv. K 2 CO 3 as base in refluxing THF. The readily prepared and cost-effective substrates, N -methyl- N -tosylamides and diarylborinic acids, and the commercially available catalyst system promise a practical and efficient access to aryl ketones. [ABSTRACT FROM AUTHOR]

• Cost-effective arylboron reagent. • Good functional group compatibility. • Low loading of simple ligandless catalyst. • Mild, open-flask and base-free conditions. • High efficacy to heteroatom ortho -substituted diazoniums. A highly efficient cross-coupling of cost-effective diarylborinic acids with both isolatable and latent arenediazoniums, i.e. tetrafluoroborates and aryltriazenes, respectively, has been developed with a practical palladium catalyst system under base-free conditions in open flask at room temperature. A variety of electronically and sterically various biaryls, in particular, those bearing a coordinative ortho -substituent, could be obtained in good to excellent yields by using 0.3 mol% palladium acetate as catalyst. Features of the protocol including cost-effectiveness of diarylborinic acids, efficacy to heteroatom ortho -substituted substrates and high chemoselectivity to aryl chlorides have been clearly demonstrated in practical synthesis of fungicide Boscalid. [ABSTRACT FROM AUTHOR]

Diarylborinic acids and tetraarylboronates are described as practical aryl source for the Pd-catalyzed Suzuki coupling of carboxylic acids to yield ketones. [ABSTRACT FROM AUTHOR]