Versatile O- and S-functionalized 1,2,3-triazoliums: ionic liquids for the Baylis–Hillman reaction and ligand precursors for stable MIC-transition metal complexes

Abstract

A series of O- and S-functionalized triazolium salts display high performance in the Baylis–Hillman addition and allow the one-pot formation of MIC-transition metal complexes.

Gold(I) complexes bearing ring‐fused benzoxazine‐derived triazolylidenes and their use in C–N bond‐forming processes

“…In general, the catalytic hydrohydrazination performances of complex 2b compares well with mesoionic [MIC–Au] + catalysts reported by Manzano et al, [ 16c ] Tolentino et al, [ 16b ] and our group [ 11h,k ] in terms of catalyst loading, conversions, time, and reaction temperatures. However, its performance is still behind the [ iPr BiCAACAu] + complex recently reported by Yazdani et al [ 18 ] In terms of the hydroamination, even though complex 2b is not as active as the known Michelet L‐shaped [NHC–Au] + complex, [ 8a ] it performs similarly than the other catalysts presented in Table 6.…”

“…The new carbene‐gold peak appears in the range of 164–168 ppm in 13 C NMR, consistent with previously reported triazolylidene gold complexes. [ 11 ]…”

“…moieties also fall in the normal parameters for monodentate MIC gold complexes reported in the literature. [ 11 ]…”

Synthesis and Catalytic Activity of Coumarin‐ and Chrysin‐Tethered Triazolylidene Gold(I) Complexes

“…NMR spectroscopy studies and elemental analyses confirmed the formation of the expected Au I ‐MIC complexes 4 and 5 by the disappearance of the acidic CH + proton in the 1 H NMR (above 9 ppm), and the observation of a low field 13 C NMR signal at δ = 171.1 ppm for complex 4 and 173.2 for complex 5 , both similar to previously reported mononuclear MIC‐gold(I) complexes . Complex 4 was crystallized from a mixture of dichloromethane/pentane at room temperature and the crystal structure is depicted in Figure .…”

Palladium(ii)-Acetylacetonato Complexes with Mesoionic Carbenes: Synthesis, Structures and Their Application in the Suzuki-Miyaura Cross Coupling Reaction

“…Metal complexes of 1,2,3-triazol-5-ylidenes are used as catalysts in a variety of catalytic transformations [16,17,18,19,20,21]. For example, copper( i ) complexes have been found to be potent catalysts for the “click” reaction [29,30,31,32,33,34], while cyclization reactions can be performed using gold( i ) 1,2,3-triazol-5-ylidene complexes as catalysts [14,28,35,36,37,38,39,40,41]. Iridium( iii ) complexes were shown to be efficient catalysts in water oxidation reactions [9,42,43,44,45] as well as other oxidation reactions and transfer hydrogenations [46,47,48,49,50,51], which are also catalyzed by ruthenium( ii ) and osmium( ii ) complexes [46,47,49,50,52,53,54,55,56,57,58].…”