1448446-94-3Relevant articles and documents
Regioselective inter- and intramolecular formal [4+2] cycloaddition of cyclobutanones with indoles and total synthesis of (±)-aspidospermidine
Kawano, Mizuki,Kiuchi, Takaaki,Negishi, Shoko,Tanaka, Hiroyuki,Hoshikawa, Takaya,Matsuo, Jun-Ichi,Ishibashi, Hiroyuki
supporting information, p. 906 - 910 (2013/02/26)
This way and that way: A formal [4+2] cycloaddition between various cyclobutanones and indoles proceeded efficiently under Lewis acid catalysis (see scheme; PG = protecting group). The regioselectivity of the reaction could be controlled in such a way that each of the two possible regioisomers of a cycloaddition product could be synthesized selectively. The usefulness of this reaction for the total synthesis of hydrocarbazole natural products was demonstrated. Copyright