Facile Preparation of Aryl Sulfides Using Palladium Catalysis under Mild Conditions

Abstract

A convenient method for C-S cross-coupling of aryl bromides with various thiols has been developed that involves the use of a 1,1¢-bis(diphenylphosphino)ferrocene (DPPF)-ligated palladium complex with N,N-diisopropylethylamine (DIPEA) as the base. This coupling is tolerant of a wide range of functional groups, including hydroxy, amino, cyano, nitro, formyl, and carboxyl groups.

Benzo-thia-fused [n]thienoacenequinodimethanes with small to moderate diradical characters: the role of pro-aromaticity versus anti-aromaticity

“…The key intermediates for the synthesis of Th n -TIPS ( n = 1–3) are the dibromo-diesters 4–6 , which were first synthesized in 60–70% yield by regio-selective lithiation of the corresponding tetrabromides 1–3 followed by quenching with ethyl cyanoformate in a one-pot protocol ( Scheme 1 ). 3b , 10 Compounds 4–6 underwent palladium-catalyzed cross-coupling reaction 11 with 4- tert -butylbenzenethiol to give compounds 7–9 in 80–90% yield. Compounds 7–9 were then hydrolyzed and acidified to form diacids 10–12 in 95% yield and the diacids were converted into the corresponding carboxylic acid chlorides by reaction with thionyl chloride in dry dichloromethane (DCM).…”

Iron-Catalyzed Cross-Coupling of Unactivated Secondary Alkyl Thio Ethers and Sulfones with Aryl Grignard Reagents

“…This preparation is based on a previously reported method for the palladium-catalyzed cross-coupling of alkyl thiols with aryl halides. 101 i -Pr 2 NEt (142 mg, 192 μL, 1.10 mmol, 1.1 equiv) and 7 (166 mg, 170 μL, 1.00 mmol, 1.0 equiv) were added sequentially to a stirred solution of 8-(trifluoromethanesulfonyloxy)quinoline 102 (277 mg, 1.00 mmol, 1.0 equiv), Pd 2 (dba) 3 (9.2 mg, 0.01 mmol, 1 mol %) and dppf (11.1 mg, 0.02 mmol, 2 mol %) in toluene (1.0 mL) in an oven-dried, one-piece, 5-mL, round-bottomed flask/water-jacketed reflux condenser equipped with a stirrer bar, rubber septum, and argon inlet. The resultant orange solution was heated to reflux for 3 h, and was then allowed to cool to rt.…”

Inhibition of Leishmania infantum trypanothione reductase by diaryl sulfide derivatives

“…Compound RDS 777 was synthesized as previously described in the literature 13 ; however, we decided to modify the second reaction step applying a modified Buchwald-Hartwig C-S cross coupling reaction 14 , as depicted in Scheme 1 , in order to avoid the use of thiophenol potassium salt (difficult to handle) and reduce the reaction time required, in spite of its reduced yield. Melting point (°C), recrystallization solvent, yield (%), chromatographic system, IR, 1H-NMR, formula, Mr and analyzed elements for derivatives RDS 738 and RDS 777 are described in literature 12 , 13 .…”