1201-73-6Relevant articles and documents
Synthesis of indolo[2,3-a]quinolizine and hexahydro-1H-indolizino[8,7-b] indole derivatives by cascade condensation, cyclization, and Pictet-Spengler reaction: An application to the synthesis of (±)-harmicine
Sanaboina, Chakrapani,Jana, Samaresh,Chidara, Sridhar,Patro, Balaram,Raolji, Gajendrasinh Balvantsinh,Eppakayala, Laxminarayana
supporting information, p. 5027 - 5029,3 (2020/07/30)
Synthesis of indole alkaloid related compounds using Schiff base formation, intramolecular cyclization (or N-alkylation), and Pictet-Spengler reaction as a cascade one pot condensation has been reported. The cascade chemistry has been applied to the synthesis of (±)-harmicine as a key step.
Intramolecular Nucleophilic Acyl Substitution Reactions of Halo-Substituted Esters and Lactones. New Applications of Organosamarium Reagents
Molander, Gary A.,McKie, Jeffrey A.
, p. 7216 - 7227 (2007/10/02)
Intramolecular nucleophilic acyl substitution reactions involving a broad range of halo substituted carboxylic acid derivatives have been accomplished in excellent yield employing samarium(II) iodide as the reductive coupling agent.Although particular substrates cyclized most effectively in THF in the presence of tripiperidinophosphine oxide, carboxylic acid esters, the focus of this report, cyclize equally well without such an additive in the presence of a catalytic quantity of iron(III) complexes.Thus a comprehensive series of halo substituted esters were cyclized in excellent yield to the corresponding 4-, 5-, and 6 -membered carbocycles.The reaction is extremely mild and selective as demonstrated by experiments wherein alkyl chlorides, acetals, and olefins remain completely intact under the reaction conditions.In addition to introducing a convenient procedure for preparing stereodefined spirocyclic systems, a new ring expansion sequence has been developed that appears extremely general for the preparation of various ring systems.
