Iron-catalysed asymmetric tandem spiro-cyclization using dioxygen in air as the hydrogen acceptor.
A tandem combination of ortho-quinone methide (o-QM) formation/Michael addition/asymmetric dearomatization, which is catalysed by an iron-salan complex in air with high enantioselectivity, provides an efficient method for spirocyclic (2H)-dihydrobenzofuran synthesis from 2-naphthols and phenols. The key to the success of the tandem synthesis is the development of aerobic oxidative o-QM formation.
Department of Chemistry, Graduate School of Science, Kyushu University, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
Takuya
T
Oguma
Tsutomu
T
Katsuki
D000388:Air; D002384:Catalysis; D003500:Cyclization; D006859:Hydrogen / Q000737:chemistry*; D045563:Indolequinones / Q000737:chemistry*; D007501:Iron / Q000494:pharmacology*; D015394:Molecular Structure; D009284:Naphthols / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry; D013141:Spiro Compounds / Q000138:chemical synthesis*; D013237:Stereoisomerism
D045563:Indolequinones; D009284:Naphthols; D010636:Phenols; D013141:Spiro Compounds; C068040:quinone methide; D006859:Hydrogen; D007501:Iron; C028405:2-naphthol; D010100:Oxygen