Preparation of Enynes by Elimination

The (l-ethynyl)-2-propenyl acetate derivative 111 undergoes an interesting PdCl2(PhCN)2-catalyzed cyclization to form the 2-cyclopentenone 112[47], A Pd-carbene complex is assumed to be an intermediate of the formation of 112. 

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Mandai, M. Ogawa, H. Yamaoki, T. Nakata, H. Murayama. M. Kawada, and J. Tsuji, Tetrahedron Lett, 32, 3397 (1991). 

Murahashi, Y. Imada, T. Mori and T. Kitamura, Abstr. Jpn Chem. Soc. Anna. Meeting //, 345 (1993). 

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