Cross-coupling reactions catalyzed by P, O chelate palladium complexes at room temperature

Synthesis of New 2-Arylbenzo[b]furan Derivatives via Palladium-Catalyzed Suzuki Cross-Coupling Reactions in Aqueous Media

A series of novel benzofuran derivatives containing biaryl moiety were designed and synthesized by the Suzuki cross-coupling reactions. The reactions, performed in the presence of K₂CO₃, EtOH/H₂O and Pd(II) complex as catalyst, gave the corresponding products in good to excellent yields. The methodology allows the facile production of heterobiaryl compounds, a unique architectural motif that is ubiquitous in medicinal chemistry.

A simple hydrophilic palladium(II) complex as a highly efficient catalyst for room temperature aerobic Suzuki coupling reactions in aqueous media

A study on room temperature Suzuki cross-coupling in an aqueous medium was carried out using a simple hydrophilic palladium (II) complex, trans-PdCl₂(NH₂CH₂COOH)₂ as catalyst in the presence of K₂CO₃ in air. This approach with a comparatively inexpensive and hydrophilic catalyst, mild reaction condition and aqueous media exhibits excellent catalytic activity towards the Suzuki coupling of aryl bromides and arylboronic acids, and good yields were obtained in the Suzuki coupling of activated aryl chlorides.

A trinuclear palladium(II) complex containing N,S-coordinating 2-(benzylsulfanyl)anilinide and 1,3-benzothiazole-2-thiolate ligands with a central square-planar PdN4 motif

The reaction of dichlorido(cod)palladium(II) (cod = 1,5-cyclooctadiene) with 2-(benzylsulfanyl)aniline followed by heating in N,N-dimethylformamide (DMF) produces the linear trinuclear Pd3 complex bis(μ2-1,3-benzothiazole-2-thiolato)bis[μ2-2-(benzylsulfanyl)anilinido]dichloridotripalladium(II) N,N-dimethylformamide disolvate, [Pd3(C7H4NS2)2(C13H12NS)2Cl2]·2C3H7NO. The molecule has -1 symmetry and a Pd...Pd separation of 3.2012 (4) Å. The outer Pd(II) atoms have a square-planar geometry formed by an N,S-chelating 2-(benzylsulfanyl)anilinide ligand, a chloride ligand and the thiolate S atom of a bridging 1,3-benzothiazole-2-thiolate ligand, while the central Pd(II) core shows an all N-coordinated square-planar geometry. The geometry is perfectly planar within the PdN4 core and the N-Pd-N bond angles differ significantly [84.72 (15)° for the N atoms of ligands coordinated to the same outer Pd atom and 95.28 (15)° for the N atoms of ligands coordinated to different outer Pd atoms]. This trinuclear Pd3 complex is the first example of one in which 1,3-benzothiazole-2-thiolate ligands are only N-coordinated to one Pd centre. The 1,3-benzothiazole-2-thiolate ligands were formed in situ from 2-(benzylsulfanyl)aniline.

Palladium-catalyzed Suzuki-Miyaura coupling of aryl sulfamates with arylboronic acids

Readily available NHC-Pd(II)-Mp complexes 2 showed efficient catalytic activity toward the Suzuki-Miyaura coupling of aryl sulfamates with arylboronic acids or potassium phenyltrifluoroborate, giving the expected coupling products in good to high yields. It should be noted that this is the first example so far of the phosphine-free, NHC-Pd(II) complexes catalyzed Suzuki-Miyaura coupling of aryl sulfamates with arylboronic acids.