Organo-silicon compoundsS 0060 DOI: 10.1002/chin.201145174

Iterative Dianion Relay Along the Ring: Formation of gem-Bis(trimethylsilyl) Cyclopentenones from 2,5-Bis(trimethylsilyl) Oxycyclopentadienyl Dianions and Acid Chlorides. — Reaction of dilithiobutadienes like (I) with aroyl chlorides contain-ing electron-withdrawing groups (III) proceeds with C—C bond formation and double silyl shift to give gem-bis(trimethylsilyl)cyclopentenones (IV) in good yields. In con-trast, reaction with bulky or electron-rich aroyl chlorides, e.g. (V) or (VIII), gives a dif-ferent product (VI) and (X), resp., via C—O bond formation and double silyl shift. The presence of THF, however, is able to trigger Brook-type rearrangement to give the C—C bond formation products (IX). — (LI, H.; LIU, L.; WANG, Z.; ZHAO, F.; ZHANG, S.; ZHANG, W.-X.; XI*, Z.; Chem. Eur. J. 17 (2011) 27, 7399-7403, http://dx.doi.org/10.1002/chem.201100830 ; Beijing Natl. Lab. Mol. Sci., Coll. Chem., Peking Univ., Beijing 100871, Peop. Rep. China; Eng.) — Mischke

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