a mild and selective catalytic aerobic oxidation process of olefins. This catalytic aerobic oxidation reaction was designed based on experimental and spectroscopic evidence assessing the reduction of atmospheric oxygen using a ferric porphyrin complex and pinacolborane to form a ferric boroperoxo porphyrin complex as an oxidizing species. The ferric boroperoxo porphyrin complex can be utilized as an
Indium(<scp>i</scp>)-catalyzed alkyl–allyl coupling between ethers and an allylborane
作者:Hai Thanh Dao、Uwe Schneider、Shū Kobayashi
DOI:10.1039/c0cc03673k
日期:——
An efficient method for alkylâallyl cross-coupling between ethers and a 9-BBN-derived allylborane catalyzed by indium(I) triflate has been developed. The allylborane proved to be essential to obtain the desired products in high yields. The reaction displayed good substrate scope including high functional group tolerance.
corresponding styrenes usingnitrosoniumtetrafluoroborate as the nitrosation reagent in pyridine (basic media) or dichloromethane (neutral media). Acid‐sensitive functional groups were tolerated under these conditions. The probable reaction mechanism was elucidated. The experimental results support an ionic reaction pathway in contrast to the conventional acidic conditions with a radical mechanism.
Synthesis of 2-phenyl-2-cycloalkenones via palladium-catalyzed tandem epoxide isomerization-intramolecular aldol condensation
作者:Ji-Hyun Kim、Robert J. Kulawiec
DOI:10.1016/s0040-4039(98)00513-9
日期:1998.5
We have extended the scope of our palladium-catalyzed tandem epoxide isomerization/aldol condensation reaction to encompass intramolecular condensations, which provide facile access to conjugatedcycloalkenones from epoxy aldehydes or diepoxides. For example, reaction of 5,6-epoxy-6-phenylhexanal with Pd(OAc)2-PBu3 catalyst in the presence of NaHCO3 and 3Å molecular sieves forms 2-phenyl-2-cyclopentenone
formations between allyl carbonates and nontoxic allyl, allenyl, or propargyl boronates. This report represents the first use of these types of boronicesters in this particular context. The present transformations proceeded with high selectivity under remarkably mild conditions, and various functional groups including an aldehyde function proved to be compatible. In addition, several boronates were found