[2p+2s] Type Cycloaddition Reactions of Naphtho[b]cyclopropene with Trithiocarbonyl Compounds to Form 1,3-Dihydronaphtho[2,3-c]thiophene Derivatives

• DOI: 10.3987/com-01-9286
• Publication Date: 2009-03-05T03:43:57Z
• Authors: Katsuhiro Saito; Yasuhiro Ohzone; Yoji Kondo; Katsuhiko Ono; Masakazu Ohkita
• Keywords: 01 natural sciences; 0104 chemical sciences

Reactions of naphtho[b]cyclopropene with trithiocarbonyl derivatives in chloroform afforded 1,3-dihydrobenzo[2,3-c]thiophene derivatives in moderate yields through a [2π+2σ] type cycloaddition process. The similar reaction with a dithiocarbonate compound gave a recovery of the starting material. A reaction with thiotropone resulted in a [8π+2σ] type adduct in 5% yield. Solvent effects on the product yields revealed that the reactions proceeded via ionic intermediates.