Water-soluble SNS cationic palladium(II) complexes and their Suzuki–Miyaura cross-coupling reactions in aqueous medium

• Alphonse Fiebor,
• Richard Tia,
• Banothile C. E. Makhubela and
• Henok H. Kinfe

Beilstein J. Org. Chem. 2018, 14, 1859–1870, doi:10.3762/bjoc.14.160

• investigation of the mechanism of the reaction revealed that a Pd(II) to Pd(IV) route is the more likely pathway which was further supported by computational studies. Keywords: cationic palladium(II) complexes; Pd(II)/Pd(IV) complexes; SNS pincer complexes; Suzuki–Miyaura; Introduction The Suzuki–Miyaura C–C

• coupling partners. Encouraged by the high hydrophilicity and the potential activity of such complexes, we are interested in the synthesis of cationic palladium(II) SNS pincer complexes of the general structure 17 (Figure 2b) having rigid fused cyclic rings imparted by a pyridine backbone; and systematic

Cationic Pd(II)-catalyzed C–H activation/cross-coupling reactions at room temperature: synthetic and mechanistic studies

• Takashi Nishikata,
• Alexander R. Abela,
• Shenlin Huang and
• Bruce H. Lipshutz

Beilstein J. Org. Chem. 2016, 12, 1040–1064, doi:10.3762/bjoc.12.99

• Takashi Nishikata Alexander R. Abela Shenlin Huang Bruce H. Lipshutz Department of Chemistry & Biochemistry, University of California, Santa Barbara, CA 93106, USA 10.3762/bjoc.12.99 Abstract Cationic palladium(II) complexes have been found to be highly reactive towards aromatic C–H activation of

• arylureas at room temperature. A commercially available catalyst [Pd(MeCN)4](BF4)2 or a nitrile-free cationic palladium(II) complex generated in situ from the reaction of Pd(OAc)2 and HBF4, effectively catalyzes C–H activation/cross-coupling reactions between aryl iodides, arylboronic acids and acrylates

• palladacycle; (2) reaction of the cationic palladacycle with an aryl iodide, arylboronic acid or acrylate, and (3) regeneration of the active cationic palladium catalyst. The reaction between a cationic palladium(II) complex and arylurea allowed the formation and isolation of the corresponding palladacycle

A modular approach to neutral P,N-ligands: synthesis and coordination chemistry

• Vladislav Vasilenko,
• Torsten Roth,
• Clemens K. Blasius,
• Sebastian N. Intorp,
• Hubert Wadepohl and
• Lutz H. Gade

Beilstein J. Org. Chem. 2016, 12, 846–853, doi:10.3762/bjoc.12.83

• cationic palladium species [2a-PdCl]BF4, which is dimeric in the solid state [11]. Similarly, Pd(allyl) complexes of ligands 2a, 5 and 7 were obtained from mixtures of the respective ligand, [Pd(allyl)Cl]2 and AgBF4 or AgOTf as the chloride scavenger in DCM (Figure 5B). We were able to obtain single

Recent advances in transition-metal-catalyzed intermolecular carbomagnesiation and carbozincation

• Kei Murakami and
• Hideki Yorimitsu

Beilstein J. Org. Chem. 2013, 9, 278–302, doi:10.3762/bjoc.9.34

• salt, (R)-tol-BINAP, and zinc triflate and subsequent quenching with benzoyl chloride afforded 3h in 75% yield with 93% ee. The addition of zinc triflate may help the formation of a more reactive cationic palladium(II) species. Under similar conditions, Lautens also reported palladium-catalyzed

Cationic gold(I) axially chiral biaryl bisphosphine complex-catalyzed atropselective synthesis of heterobiaryls

• Tetsuro Shibuya,
• Kyosuke Nakamura and
• Ken Tanaka

Beilstein J. Org. Chem. 2011, 7, 944–950, doi:10.3762/bjoc.7.105

• 6-endo-dig and 6-exo-dig cyclizations [39][40][41], the use of these gold(I) complexes gave almost racemic products [42]. Fortunately, cationic palladium(II)/axially chiral biaryl bisphosphine complexes were found to be effective catalysts, and a cationic palladium(II)/(S)-xyl-Segphos complex showed

• the highest enantioselectivity (Scheme 2) [42]. In addition, the cationic palladium(II)/axially chiral biaryl bisphosphine complexes were able to catalyze the asymmetric intramolecular hydroarylation of N-aryl-arylethynylamides leading to axially chiral 4-aryl-2-quinolinones, and the cationic

• cationic palladium(II)/(S)-xyl-H8-BINAP-complex catalyzed atropselective intramolecular hydroarylation of alkynes, the presence of the 2-methoxy-substituted aryl group at the alkyne terminus was important for the realization of both high reactivity and enantioselectivity [40]. Similarly, the reaction of 2