Desulfitative Cross-coupling Reactions Research Articles

Synthesis of arylstannanes by palladium-catalyzed desulfitative coupling reaction of sodium arylsulfinates with distannanes

A novel Pd-catalyzed desulfitative cross-coupling reaction of sodium arylsulfinates with hexaalkyl distannanes is realized, allowing the facile synthesis of functionalized arylstannanes with moderate to excellent yields. The successful implement of gram-scale synthesis and tandem Stille coupling reaction demonstrates the potential applications of this method in organic synthesis.

Three successive and regiocontroled palladium cross-coupling reactions to easily synthesize novel series of 2,4,6-tris(het)aryl pyrido[1',2':1,5]pyrazolo[3,4-d]pyrimidines.

The first access to tris(het)arylated pyrido[1′,2′:1,5]pyrazolo[3,4-d]pyrimidine derivatives is reported. The series were generated from 4-chloroaminopyridinium, which afforded the key intermediate bearing three leaving groups, i.e. a C-2 methylsulfanyl, a lactame carbonyl group in C-4 and a chlorine atom in C-6. The regioselective reactions led to the tris(het)aryl derivatives with satisfying to high yields. The three successive cross-coupling reactions occurred first in C-6 by the displacement of chlorine, next in C-4 position by a sequential Pd-catalyzed phosphonium coupling and finally in C-2 under a Pd/Cu-catalyzed desulfitative cross-coupling reaction. The optimization and scope of each reaction are discussed and the original compounds characterized.

Recent advances in decarboxylative and desulfitative cross-coupling reactions catalyzed by transition-metals through C-H activation

The transition-metal catalyzed carbon-hydrogen bond activation and functionalization reaction is one of the versatile methods to construct the carbon-carbon bond in organic synthesis, which has become a hot topic in current organic chemistry and has been widely used in the synthesis of natural products and pharmaceutical intermediates. In recent years, decarboxylative and desulfitative cross-coupling reactions have been received much attention in organic synthesis with rich achievements. The cross-coupling reactions constitute advantageous alternatives to traditional cross-coupling or addition reactions involving preformed organometallic reagents. In general, the transition metals involved in the reactions, including palladium, copper, silver, rhodiun, iron and so on. This review mainly covers the recent advances in the versatility and practicality of decarboxylative coupling reactions and desulfitative coupling reactions catalyzed by transition-metal catalysts through the corresponding carbon-hydrogen bonds activation and their further functionalizations.

New synthetic approach for the preparation of 2-aryl-thiazolo[4,5-b]pyridines via Liebeskind–Srogl reaction

Abstract The potentially bioactive 2-aryl-thiazolo[4,5- b ]pyridines were synthesized via palladium-catalyzed desulfitative cross-coupling reaction between multisubstituted thiazolo[4,5- b ]pyridine thioethers and boronic acids. Yields of 48%–94% were obtained with copper(I) thiophene-2-carboxylate in the system.

Highly Regioselective Arylation of 1,2,3-Triazole N-Oxides with Sodium Arenesulfinates via Palladium-Catalyzed Desulfitative Cross-Coupling Reaction

A convenient and highly regioselective palladium-catalyzed direct C5-arylation of 1,2,3-triazole N-oxides was developed in the presence of silver carbonate and tripotassium phosphate. This protocol allowed use of sodium arylsulfinates, diphenylphosphine oxide, and triphenylphosphine as arylating reagents to produce 2-aryl-5-aryl-1,2,3-triazole N-oxides in good to excellent yields, providing a complement to the existing methods for the direct arylation of 1,2,3-triazole N-oxides.

Palladium-catalyzed desulfitative cross-coupling of arylsulfinates with arylboronic acids

Palladium (Pd)-catalyzed desulfitative cross-coupling reactions of sodium arylsulfinates with a wide variety of arylboronic acids were achieved in good to excellent yields under simple aerobic conditions. These catalytic reactions could be accelerated by addition of a catalytic amount of Cu(II) salts as co-catalyst. Moreover, these reactions were tolerant to all of the tested functional groups, making them attractive alternatives to the traditional cross-coupling reactions.

Palladium-Catalyzed Desulfitative Cross-Coupling Reaction of Sodium Sulfinates with Benzyl Chlorides

A palladium-catalyzed approach for the synthesis of diarylmethanes from sodium sulfinates and benzyl chlorides is described. Various aromatic sodium sulfinates were used as aryl sources via extrusion of SO2 and gave the diarylmethanes in moderate to good yields.

Palladium‐Catalyzed Desulfitative Mizoroki–Heck Couplings of Sulfonyl Chlorides with Mono‐ and Disubstituted Olefins: Rhodium‐Catalyzed Desulfitative Heck‐Type Reactions under Phosphine‐ and Base‐Free Conditions

New conditions have been found for the desulfitative Mizoroki-Heck arylation and trifluoromethylation of mono- and disubustituted olefins with arenesulfonyl and trifluoromethanesulfonyl chlorides. Thus (E)-1,2-disubstituted alkenes with high stereoselectivity and 1,1,2-disubstituted alkenes with 12:1 to 21:1 E/Z steroselectivity can be obtained. Herrmann's palladacycle at 0.1 mol % is sufficient to catalyze these reactions, for which electron-rich or electron-poor sulfonyl chlorides and alkenes are suitable. If phosphine- and base-free conditions are required, 1 mol % [RhCl(C(2)H(4))(2)] catalyzes the desulfitative cross-coupling reactions. Contrary to results reported for [RuCl(2)(PPh(3))(2)]-catalyzed coupling reactions with sulfonyl chlorides, the palladium and rhodium desulfitative Mizoroki-Heck coupling reactions are not inhibited by radical scavenging agents. Possible sulfones arising from the sulfonylation of alkenes at 60 degrees C are not desulfitated at higher temperatures in the presence of the Pd or Rh catalysts.