Synthesis of the bicyclic welwitindolinone core via an alkylation/cyclization cascade reaction.
Synthesis of an advanced welwitindolinone intermediate via an alkylation/cyclization reaction is reported. The key step involves a one pot Lewis acid-mediated alkylation of a silylketene aminal with a furan alcohol followed by an intramolecular cyclization. The reaction is stereoselective and takes place at low temperature. The cycloadduct was highly functionalized and contains the welwitindolinone core structure.
Brailsford
John A
JA
Deparment of Chemistry, University of California, Irvine, 1102 Natural Sciences 2, Irvine, California, 92697-2025, USA.
Lauchli
Ryan
R
Shea
Kenneth J
KJ
D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D000478:Alkylation; D018360:Crystallography, X-Ray; D003500:Cyclization; D026121:Indole Alkaloids; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D009570:Nitriles / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
D000470:Alkaloids; D026121:Indole Alkaloids; D007211:Indoles; D009570:Nitriles; C507638:welwitindolinone A; C546298:welwitindolinone B; C092270:welwitindolinone C isothiocyanate