Syntheses of highly substituted furan and pyrrole derivatives via lithiated 3-aryl-1-methoxyallenes: Application to the synthesis of codonopsinine

Article abstract of DOI:10.1055/s-2006-949622

Lithiated 1-methoxy-3-phenylallenes were generated in situ from a phenyl-substituted propargylic ether. They smoothly combined with aldehydes, ketones, or imines to give allenyl adducts, which cyclized to highly substituted heterocycles either under basic