Quinolizidine synthesis via intramolecular immonium ion based Diels-Alder reactions. Total synthesis of (.+-.)-lupinine, (.+-.)-epilupinine, (.+-.)-cryptopleurine, and (.+-.)-julandine
Quinolizidine synthesis via intramolecular immonium ion based Diels-Alder reactions. Total synthesis of (.+-.)-lupinine, (.+-.)-epilupinine, (.+-.)-cryptopleurine, and (.+-.)-julandine