Direct synthesis of 2-arylazulenes by [8+2] cycloaddition of 2H-cyclohepta[b]furan-2-ones with silyl enol ethers. Issue 10 (8th January 2020) - Shoji, Taku
Abstract : We have developed a procedure for the direct synthesis of 2-arylazulenes. The 2-arylazulenes are formed in moderate to excellent yields by [8+2] cycloaddition of 2 H -cyclohepta[ b ]furan-2-one derivatives with aryl-substituted silyl enol ethers. Abstract : We developed a procedure for the direct synthesis of 2-arylazulenes, which were obtained in moderate to excellent yields, by [8+2] cycloaddition of 2 H -cyclohepta[ b ]furan-2-ones with aryl-substituted silyl enol ethers. The structures of some 2-arylazulenes were clarified by single-crystal X-ray analysis. The 2-phenylazulene derivatives obtained by this study showed noticeable fluorescence in acidic media.