Catalytic Sulfur-Enabled Dehydrobicyclization of 1,6-Enynes toward Arylated Indeno[1,2-c]thiophenes
Ya-Nan Wu1, Rong Fu1, Nan-Nan Wang1
1School of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University , Xuzhou 221116, PR China.
Abstract:
A new copper-catalyzed sulfur-enabled dehydrobicyclization of 1,6-enynes using potassium sulfide as a sulfurating reagent has been established, providing a straightforward access toward arylated indeno[1,2-c]thiophenes with moderate to good yields. This sulfur incorporation pathway involves Michael addition, 5-exo-dig/5-endo-trig bicyclization and dehydrogenation sequence, resulting in continuous multiple bond-forming events including C-S and C-C bonds to rapidly construct functional organic molecules.
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