Novel Synthesis of 1,4-Dialkoxy-5,6,7,8-multisubstituted-2,3-dicyanonaphthalenes through Electron Transfer from Mg Metal and Efficient Development of New Naphthalocyanines
An intriguing, facile, and efficient oxidation and cyclization of alkynes catalyzed by Pd(OAc)2 in a fluorous biphasic system of N,N-dimethylacetamide (DMA) and perfluorodecalin directly with molecular oxygen is described, which opens an efficient access to tetrasubstituted furans. Under the optimized conditions, intermolecular reaction between diverse alkynes provides the corresponding mixture of regioisomers with appreciable selectivity. Intramolecular oxidation and cyclization of alkynes are also successfully demonstrated. The reaction proceeds efficiently under mild conditions with atmospheric oxygen as the sole oxidant.
Synthesis of Tetrasubstituted Furans via Sequential Pd(OAc)2/Zn(OTf)2-Catalyzed Oxidation and Cyclization of Aromatic Alkynes with Molecular Oxygen
作者:Huanfeng Jiang、Azhong Wang、Qiuxiang Xu
DOI:10.1055/s-0028-1088216
日期:2009.4
The development of a new method for the synthesis of tetrasubstituted furans using aromatic alkynes is reported. The strategy involves a tandem process of palladium-catalyzed oxidation and Zn(OTf)2-catalyzed cyclization in the presence of molecular oxygen.
Unexpected Base-Promoted Synthesis of Tetrasubstituted Furans via Palladium-Catalyzed Oxidation and Cyclization of Carbon-Carbon Triple Bond with Molecular Oxygen
A new approach to the synthesis of tetrasubstituted furans using aromatic alkynes catalyzed by PdCl2 in DMA (N,N-dimethylacetamide)-H2O with dioxygen as the sole oxidant is described, in which the oxygen atom of the furan was from water. The preliminary mechanistic understanding of this transformation was investigated.
Site-selective Suzuki–Miyaura cross-coupling reactions of 2,3,4,5-tetrabromofuran
作者:Munawar Hussain、Rasheed Ahmad Khera、Nguyen Thai Hung、Peter Langer
DOI:10.1039/c0ob00695e
日期:——
SuzukiâMiyaura reactions of 2,3,4,5-tetrabromofuran allow a convenient and site-selective synthesis of mono-, di- and tetraarylfurans which are not readily available by other methods.