Oxidative dimerization of 2-oxindoles promoted by KO(t)Bu-I₂: total synthesis of (±)-folicanthine.
A 'transition-metal-free' oxidative coupling of 2-oxindoles has been demonstrated in the presence of 1.2 equiv each of potassium tert-butoxide and iodine. The method yields a diverse range of structurally different homo- and heterodimerized 2-oxindoles bearing vicinal all-carbon quaternary centers of great synthetic importance. A radical-driven pathway has been tentatively proposed.
Department of Chemistry, Indian Institute of Science Education and Research, Bhopal - 462 066, MP, India.
Santanu
S
Ghosh
Department of Chemistry, Indian Institute of Science Education and Research, Bhopal - 462 066, MP, India.
Saikat
S
Chaudhuri
Department of Chemistry, Indian Institute of Science Education and Research, Bhopal - 462 066, MP, India.
Alakesh
A
Bisai
D002384:Catalysis; D019281:Dimerization; D006847:Hydrocarbons, Iodinated / Q000737:chemistry*; D026121:Indole Alkaloids / Q000737:chemistry; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D058451:Oxidative Coupling; D000078183:Oxindoles; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
D006847:Hydrocarbons, Iodinated; D026121:Indole Alkaloids; D007211:Indoles; D000078183:Oxindoles; D011758:Pyrroles; C521485:folicanthine; C022960:2-oxindole