A palladium-catalyzed [2 + 2 + 1] domino annulation of 3-iodochromones, α-bromo carbonyl compounds, and tetracyclododecene (TCD) is described. This approach provides a facile, efficient and atom-economical route to a variety of chromone-containing polycyclic compounds bearing fused/bridged-ring systems in good yields (up to 81%) with excellent diastereoselectivities (99 : 1 dr in all cases).
The nano-Al2O3-promoted epoxidation of alkenes with molecular oxygen as the oxidant has been developed, providing an efficient route to a variety of epoxides in moderate to excellent yields. The environmentally friendly and efficient nano-Al2O3 catalyst could be easily recovered and reused five times without significant loss of activity.
Dechlorination Reactions of Hexachlorinated Polycyclic Compounds Using Ultra-Sound Radiation
作者:Valentim Emilio Uberti Costa、Maria E. S. Möllmann、Valéria Belli Riatto
DOI:10.1080/00397919508015890
日期:1995.7
Abstract Dechlorination reactions of exo-endo and endo-endo perhalogenated tetracyclic compounds with Li/t-BuOH/THF system, when subjected to simultaneous ultra-sound irradiation, led to exceptionally high yields (77-95%) of the corresponding hydrocarbons.
Epoxidation of Olefms with Molecular Oxygen and Alcohol Catalyzed by Bis(2-alkyl-1,3-diketonato)oxovanadium(IV)
作者:Toshihiro Takai、Tohru Yamada、Teruaki Mukaiyama
DOI:10.1246/cl.1990.1657
日期:1990.9
By combined use of molecular oxygen (oxidant) and secondary or primary alcohol (reductant) in the presence of a catalytic amount of bis(2-alkyl-1,3-diketonato)oxovanadium(IV) complexes, norbornene analogues are monooxygenated into the corresponding epoxides in good yields.
A Novel Method for the Preparation of Acid-Sensitive Epoxides from Olefins with the Combined Use of Molecular Oxygen and Aldoacetal Catalyzed by a Cobalt(II) Complex
An efficient synthesis of acid-sensitive epoxides, such as chromene oxide or epoxide of γ,δ-unsaturated alcohol, was successfully achieved by the oxygenation of corresponding olefins with the combined use of an atmospheric pressure of molecular oxygen and aldoacetal catalyzed by a cobalt(II) complex coordinated with the 1,3-diketone ligand. The reactions proceeded under mild and neutral conditions