Synlett 2006(13): 2145-2147  
DOI: 10.1055/s-2006-949607
LETTER
© Georg Thieme Verlag Stuttgart · New York

Palladium-Catalyzed Coupling Reaction of Diaryl Dichalcogenide with Aryl Bromide Leading to the Synthesis of Unsymmetrical Aryl Chalcogenide

Shin-ichi Fukuzawa*, Daisuke Tanihara, Satoshi Kikuchi
Department of Applied Chemistry, Institute of Science and Engineering, Chuo University, Kasuga, Bunkyo-ku, Tokyo 112-8551 Japan
Fax: +81(3)38171895; e-Mail: fukuzawa@chem.chuo-u.ac.jp;
Further Information

Publication History

Received 14 June 2006
Publication Date:
09 August 2006 (online)

Abstract

An efficient cross-coupling reaction of diphenyl disulfide or diselenide with substituted aryl bromides using PdCl2(dppf) and zinc has been developed. This method gave functionalized unsymmetrical aryl sulfides and selenides in good to excellent yields under neutral conditions.

10

The copper-catalyzed reaction of bromobenzene with diphenyl disulfide produced only a 34% yield of diphenyl sulfide. See ref. 7a.

11

Typical experimental procedure: Diphenyl disulfide (109 mg, 0.5 mmol), PdCl2(dppf) (37 mg, 0.05 mmol), and zinc (80 mg, 1.2 mmol), were placed in a round-bottom flask containing a stirring bar, and a THF solution (5 mL) of the aryl bromide (1.0 mmol) was then added to the flask, and the resulting mixture was heated at reflux for 24 h. After cooling to r.t., the mixture was diluted with Et2O (30 mL). The precipitate was removed by filtration and the filtrate was washed with brine and dried (Na2SO4). A GC-MS analysis of the ethereal solution showed the presence of the corresponding unsymmetrical sulfide, and the yield was determined using biphenyl as an internal standard. The aryl sulfide was isolated by PTLC and fully characterized.

12

The reaction with p-iodonitrobenzene proceeded to give the corresponding aryl sulfide in 82% yield.

13

Magnesium was used instead of zinc for the reaction with 2-bromothiophene.