Synthesis and structure of trans-bis(1,4-dimesityl-3-methyl-1,2,3-triazol-5-ylidene)palladium(II) dichloride and diacetate. Suzuki–Miyaura coupling of polybromoarenes with high catalytic turnover efficiencies

Abstract

Summary trans-Bis(1,4-dimesityl-3-methyl-1,2,3-triazol-5-ylidene)palladium(II) dichloride has been shown to be an excellent catalyst for the multiple Suzuki–Miyaura coupling reactions of polybromoarenes to the corresponding fully substituted polyarylarenes. The reactions proceeded in excellent yields and with high turnover numbers. With 1,4-dibromobenzene the catalyst was found to be active for up to 13 consecutive cycles with a turnover number of 1260. The polyarylarenes were obtained in pure form after crystallization once without recourse to chromatographic purification. The single-crystal X-ray structures of the chloro (1) as well as the corresponding acetato (2) complexes are also reported and compared with the corresponding complexes of 1,4-diphenyl-3-methyl-1,2,3-triazol-5-ylidene as the ligand.

Synthesis of new functionalized triarylmethanes via Suzuki cross-coupling and Heck-type vinylation reactions

“…Moreover, this kind of TRAM could not be synthesized by Friedel-Crafts alkylation reactions of aldehydes. Double Suzuki-Miyaura coupling reactions using palladium catalysts have been repeatedly reported in organic synthesis [31][32][33][34][35]. Surprisingly, one-pot, double Suzuki coupling reactions of TRAM 10g with two-fold amounts of 11a and 11c under optimal reaction conditions resulted in products 6k and 6l in 78% and 54% yields, respectively.…”

Crystal structure of 1-mesityl-3-methyl-4-phenyl-1H-1,2,3-triazol-3-ium iodide

“…For classical Arduengo-type imidazol-2-ylidene N-heterocyclic carbenes (NHCs), see: Arduengo et al (1995); Mathew et al (2008). For similar 1-mesityl-3-methyl-4-phenyl-1H-1,2,3triazol-3-ium structures and some complexes, see: Saravanakumar et al (2011); Hohloch et al (2011Hohloch et al ( , 2013; Shaik et al (2013) Hydrogen-bond geometry (Å , ).…”

Synthesis of the First Resorcin[4]arene-Functionalized Triazolium Salts and Their Use in Suzuki–Miyaura Cross-Coupling Reactions

“…Their precursors, namely 1,2,3-triazoles, are easily accessible through copper-catalyzed Huisgen [3 + 2] click-type cycloaddition of azides and alkynes (CuAAC) [6,7], followed by N3-quaternarization. The resulting 1,2,3-triazolium salts can then be converted to transition metal complexes that, i.a., are suitable for Suzuki-Miyaura [8][9][10][11][12][13][14][15][16][17][18], Mizoroki-Heck [19,20], and Sonogashira coupling reactions [19,21], as well as for various reduction or oxidation reactions [22][23][24][25][26][27], and C-heteroatom bond forming reactions [28][29][30][31][32].…”

“…Synthesis of 1-(2,6-Dimethoxyphenyl)-3-methyl-4-phenyl-1H-1,2,3-triazolium iodide(11) 3.10.1.Step 1: Synthesis of 1-(2,6-Dimethoxyphenyl)-4-phenyl-1H-1,2,3-triazole To a solution of 2-azido-1,3-dimethoxybenzene (0.480 g, 2.68 mmol), CuSO4 •5H 2 O (0.067 g, 0.27 mmol), and sodium ascorbate (0.053 g, 0.27 mmol) in DMF (10 mL) phenylacetylene was added (0.29 mL, 2.68 mmol). The mixture was stirred for 36 h at 100 • C, then cooled to room temperature.…”