The base-catalyzed reaction of hydroxy lactone 1 with several cyclic and acyclic vinylogous amides and 1, 3-dicarbonyl compounds was found to provide a smooth method to prepare pyrrole, furan, tetrahydroindole, and tetrahydrobenzofuran ring systems. The reaction of 1 with the cyclic enaminone 2 affords 3 which can be isomerized to the tetrahydroindole-2- acetic acid 4. The reaction of 1 with 6 and 8 produces, after esterification, the methyl ...
[Mori, Miwako; Akashi, Masaya; Hori, Masanori; Hori, Katsutoshi; Nishida, Mayumi; Sato, Yoshihiro Bulletin of the Chemical Society of Japan, 2004 , vol. 77, # 9 p. 1655 - 1670]
