2006

Cyclopentane derivativesQ 0030 Metal-Mediated Efficient Synthesis, Structural Characterization, and Skeletal

Rearrangement of Octasubstituted Semibullvalenes. — Five semibullvalenes are prepared by CuCl-mediated C—C bond forming of dilithiodienes derived from diio-dides (I) or (IV). Tetraalkyl-substituted semibullvalenes of type (II) undergo transfor-mation into cyclooctatetraenes (III) upon heating, whereas (V) affords a mixture of products including pentalene (VI). The latter compound is also obtained by acidic work-up of the reaction mixture derived from (IV) and by acidic treatment of (V). These transformations are not observed for semibullvalenes of type (II). — (WANG, C.; YUAN, J.; LI, G.; WANG, Z.; ZHANG, S.; XI*, Z.; J. Am. Chem. Soc. 128 (2006) 14, 4564-4565; Key Lab. Bioorg. Chem. Mol. Eng., Minist. Educ., Coll. Chem., Peking Univ., Beijing 100871, Peop. Rep. China; Eng.) — Klein

32- 082