C1-C5 Photochemical Cyclization of Enediynes [J. Am. Chem. Soc. 2002, 124, 9052-9053]. Igor V. Alabugin* and Sergei V. Kovalenko Page 9052. It was brought to our attention that a topologically similar (but mechanistically different from our finding) C1C5 cyclization of enediyne radical-cations was reported earlier (Ramkumar, D.; Kalpana, M.; Varghese, B.; Sankararaman, S.; Jagadeesh, M. N.; Chandrasekhar, J. J. Org. Chem., 1996, 61, 2247). Later, it was shown (Schmittel, M.; Kiau, S. Liebigs Ann./ Recueil 1997, 1391-1399) that under a variety of conditions this transformation proceeds through a simple acid-catalyzed cyclization. We thank Professor Michael Schmittel for bringing this information to our attention. JA025117X 10.1021/ja025117x Published on Web 11/16/2002
10.1021/ja025117x CCC: $22.00 © 2002 American Chemical Society
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