Half-sandwich (η⁵-Cp*)Rh(iii) complexes of pyrazolated organo-sulfur/selenium/tellurium ligands: efficient catalysts for base/solvent free C–N coupling of chloroarenes under aerobic conditions

Abstract

<p>Three new Rh(<sc>iii</sc>) complexes of organochalcogen (S/Se/Te) ligands were synthesized and along with a co-catalyst Cu(OAc)₂, used for the base/solvent free catalysis of Buchwald type C–N coupling of amines and aryl chlorides under aerobic conditions.</p>

Cu/Mn-Catalyzed C–N Cross-Coupling Reaction of Aryl Chlorides and Amines Promoted by a Polyamidoamine Dendrimer

“…Moreover, Cu/Mn bimetallic catalysis enables the carbonylative Suzuki-Miyaura coupling reaction [24][25][26][27] . Various bimetallic system in homogeneous media has been also explored for the C-N coupling reaction, the Half-Sandwich (η5-Cp*)Rh(III) complex of pyrazolated organo-Sulfur/ Selenium/ Tellurium ligands 28 and Cp*Co(III) and Cu(OAc)2 bimetallic system for Buchwald type C-N cross coupling of arylchlorides and amines 29 .…”

“…23 Moreover, Cu/Mn bimetallic catalysis permits a carbonylative Suzuki-Miyaura coupling reaction. [24][25][26][27] Various bimetallic systems in homogeneous media have been also explored for C-N coupling reactions, including the half-sandwich (η 5 -Cp*)Rh(III) complex of pyrazolated organosulfur, organoselenium, or organotellurium ligands 28 and a Cp*Co(III)/Cu(OAc) 2 bimetallic system for Buchwaldtype C-N cross-couplings of aryl chlorides with amines. 29 Here, we report the first PAMAM-promoted, Mn/Cu bimetallic homogeneous system for the C-N cross-coupling reaction of aryl chlorides with amines.…”

Half‐Sandwich (η6‐Benzene)Ruthenium(II) Complex of Picolyl Functionalized N‐Heterocyclic Carbene as an Efficient Catalyst for Thioether Directed C−H Alkenylation of Arenes

“…Moving further to solvent optimization, below to average yield (28 %) was obtained in absence of solvent, but, surprising to us, it decreased to 18 % when toluene was used as a solvent. Other solvents such as ethyl acetate, hexane, 1,4-dioxane, and water were also failed to mimic the transformations (Entry [13][14][15][16][17][18].…”

“…Nevertheless, it is worthy to use thioether as a directing group, as under reductive conditions these groups can be easily removed. [14] Furthermore, thioether could go through a variety of useful transformations, [15][16][17] sulphur is also found in various useful molecules including functional material, organocatalyst [18][19][20][21] and water reduction catalyst. [22][23] Zhang and co-workers reported a Pd catalyzed CÀ H bond alkenylation of thioethers in 2012 (Scheme 1).…”

CO-free, aqueous mediated, instant and selective reduction of nitrobenzene via robustly stable chalcogen stabilised iron carbonyl clusters (Fe3E2(CO)9, E = S, Se, Te)

“…Due to good electron donor properties of chalcogen atoms, chalcogenide complexes have emerged as a potential alternative to phosphine complexes. Their ability to withstand air/moisture and their permanence during catalysis makes them suitable catalysts for long-duration reactions, which include C-C couplings 37,38 C-N couplings 39 and other organic transformations. 40 In addition to gaseous hydrogen, several other reducing agents have been used that allow the efficient reduction of nitrobenzene when used in combination with metals, including boranes, 41 NaBH 4 , 42 silanes 43 and hydrazine.…”