Nickel(II)‐Mediated C−S Cross‐Coupling Between Thiols and ortho‐Substituted Arylboronic Acid

Abstract

Herein, we report a C−S cross‐coupling reaction between alkyl thiols or aryl thiols and ortho‐substituted arylboronic acids that proceeds in the presence of an inexpensive and ligand‐free NiCl2 ⋅ 6H2O salt and N‐methylmorpholine, a weak base, at 25 °C in air. The presence of coordinating and electron‐withdrawing groups at the ortho‐position of the arylboronic acids played a crucial role in determining the efficiency of the reaction. X‐ray crystallographic analysis revealed that the [NiCl2(DMF)2(H2O)2] complex was formed in‐situ. The complex is an excellent precursor of the active nickel species. The reaction offers an extremely mild and operationally convenient method to access a wide variety of alkyl aryl sulfides and diaryl sulfides without using expensive transition metals, such as palladium, gold, and rhodium, and specialized and expensive ligands.

Thiolate-assisted copper(i) catalyzed C–S cross coupling of thiols with aryl iodides: scope, kinetics and mechanism

“…2 Recently, transition metal catalyzed C–S cross coupling reactions have emerged as a versatile strategy for the synthesis of aryl thioether and related sulfur containing compounds. 3 Various transition metals such as palladium, 4 nickel, 5 iron, 6 iridium, 7 ruthenium, 8 cobalt, 9 manganese, 10 gold 11 and silver 12 have been effectively employed as the catalyst in the C–S cross coupling reactions. However, the use of precious and expensive metals, the requirement of harsh reaction conditions, and high boiling point solvents in these reactions limit the applications of transition-metal catalysts from both economic as well as environmental viewpoints.…”

Transition-Metal-Catalyzed C–S, C–Se, and C–Te Bond Formations via Cross-Coupling and Atom-Economic Addition Reactions. Achievements and Challenges

“…Recently, Hanaya and co-workers described a Ni(II)mediated analogue of the Chan−Lam reaction between arylboronic acids and thiols (Scheme 212, B). 93 S-Arylation of the cysteine fragment can be carried out under the action of arylboronic acids with electron-withdrawing substituents (preferably with the NO 2 group) at the ortho position and the nickel salt Ni(OAc) 2 as a catalyst (Scheme 212, C). 735 Ni-catalyzed sulfonylation of arylboronic acids was carried out under the action of Na 2 S 2 O 5 in the presence of benzylammonium salts (Scheme 213).…”

Transition Metal CatalysedC‐SCross‐Coupling Reactions at Room Temperature.

“…Csp2-S cross-coupling reaction between alkyl/aryl thiols and ortho-substituted arylboronic acids was reported by Sugai and co-worker using ligand-free NiCl 2 ⋅6H 2 O salt and N-meth-ylmorpholine at 25 °C in air (Scheme 25). [52] The presence of coordinating and electron-withdrawing groups at the orthoposition of the arylboronic acids played a decisive role in determining the efficiency of the reaction. X-ray crystallographic analysis revealed that the [NiCl 2 (DMF) 2 (H 2 O) 2 ] complex was formed in-situ.…”