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.
Deparment of Chemistry, University of California, Irvine, 1102 Natural Sciences 2, Irvine, California, 92697-2025, USA.
John A
JA
Brailsford
Ryan
R
Lauchli
Kenneth J
KJ
Shea
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