title: Gold catalysis: phenol synthesis in the presence of functional groups.
abstract: The effect of different substituents, such as bromo, chloromethyl, hydroxymethyl, formyl, acetyl, carboxy, and acylated hydroxymethyl and ammonium groups, on the furan ring of substrates in gold-catalyzed phenol synthesis has been investigated. The furan ring was also replaced by different heterocycles, such as pyrroles, thiophenes, oxazoles, and a 2,4-dimethoxyphenyl group; gold catalysis then delivered no phenols, but occasionally other products were obtained. [Ru(3)(CO)(12)] also catalyzed the conversion of 1 at a low rate, [Os(3)(CO)(12)] failed as a catalyst, and with [Co(2)(CO)(8)] the alkyne complex 19 can be obtained, it does not lead to any phenol but reacts with norbornene to give the product of a Pauson-Khand reaction. Efforts to prepare vinylidene complexes of 1 provided the only evidence for these species; in the presence of a phosphane ligand with ruthenium an interesting deoxygenation to 22 was observed. The phenol 2 c was converted to the allyl ether, a building block for para-Claisen rearrangements, and to the aryl triflate, a building block for cross-coupling reactions.
authors.affiliation: Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany. hashmi@hashmi.de
authors.forename: A Stephen K
authors.initials: AS
authors.lastname: Hashmi
authors.forename: Jan P
authors.initials: JP
authors.lastname: Weyrauch
authors.forename: Elzen
authors.initials: E
authors.lastname: Kurpejović
authors.forename: Tanja M
authors.initials: TM
authors.lastname: Frost
authors.forename: Burkhard
authors.initials: B
authors.lastname: Miehlich
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Frey
authors.forename: Jan W
authors.initials: JW
authors.lastname: Bats