Cationic Palladium(II)-Catalyzed Addition of Arylboronic Acids to Nitriles. One-Step Synthesis of Benzofurans from Phenoxyacetonitriles

Direct palladium(II)-catalyzed synthesis of arylamidines from aryltrifluoroborates

A fast and convenient synthesis of arylamidines starting from readily available potassium aryltrifluoroborates and cyanamides is reported. The coupling was achieved by Pd(II)-catalysis in a one step 20 min microwave protocol using Pd(O₂CCF₃), 6-methyl-2,2′-bipyridyl, TFA, and MeOH, providing the corresponding arylamidines in moderate to excellent yields.

Cationic palladium complex catalyzed diastereo- and enantioselective tandem annulation of 2-formylarylboronic acids with allenoates

Cationic palladium complex [(dppp)Pd(H(2)O)(2)](2+)(BF(4)(-))(2) catalyzed tandem annulation reactions of 2-formylarylboronic acids and allenoates produce the indenol derivatives diastereo- and enantioselectively in a highly efficient way.

A New Synthetic Route of 2-Aroyl- and 2-Benzyl-Benzofurans and their Application in the Total Synthesis of a Metabolite Isolated from Dorstenia gigas

The Lewis acid-catalyzed cyclization of the (Z)-3-(dimethylamino)-2-aryloxy-1-arylprop-2-en-1-ones 4a–h leads to a regioselective and short synthesis of 2-aroylbenzofurans 2a–h. The Wolff–Kishner reduction of the latter yielded a series of substituted 2-benzylbenzofurans 3a–h. This methodology was applied in the first total synthesis of the metabolite 2-(4-hydroxybenzyl)-6-methoxybenzofuran 1, which was isolated from the tropical plant Dorstenia gigas, and obtained through a six-step route and in a 24% overall yield.

Diastereoselective Synthesis of Arylglycine Derivatives by Cationic Palladium(II)-Catalyzed Addition of Arylboronic Acids to N-tert-Butanesulfinyl Imino Esters

A cationic palladium-complex-catalyzed addition of arylboronic acids to N-tert-butanesulfinyl iminoacetates to yield the optically active arylglycine derivatives with moderate to good yield and high diastereoselectivity was developed. This reaction provides a convenient and efficient method for the synthesis of arylglycine derivatives.

Cationic Pd(II)-Catalyzed Enantioselective Cyclization of Aroylmethyl 2-Alkynoates Initiated by Carbopalladation of Alkynes with Arylboronic Acids

A cationic palladium(II)-catalyzed enantioselective intramolecular addition of vinylpalladium species to ketones initiated by the carbopalladation of alkynoates under mild conditions without a Pd(II)/Pd(0) redox system was developed with high yield and enantioselectivity. This cascade reaction provides an efficient method for the construction of optically active hydroxylactones.

CuI-catalyzed domino process to 2,3-disubstituted benzofurans from 1-bromo-2-iodobenzenes and beta-keto esters

CuI-catalyzed coupling of 1-bromo-2-iodobenzenes with beta-keto esters in THF at 100 degrees C leads to 2,3-disubstituted benzofurans. This domino transformation involves an intermolecular C-C bond formation and a subsequent intramolecular C-O bond formation process. Benzofurans with different substituents at the 5- and 6-position are accessible by employing the corresponding 1-bromo-2-iodobenzenes.