We have established that a cationic rhodium(I)-dppf complex catalyzes isomerizations of allyl propargyl ethers to allenic aldehydes in good yields from room temperature to 40 degrees C. On the other hand, carbonyl migration reactions from allenic aldehydes further proceed to give dienals in good yields at 80 degrees C.
SeO<sub>2</sub>-Mediated Oxidative Transposition of Pauson–Khand Products
作者:Sara E. Dibrell、Michael R. Maser、Sarah E. Reisman
DOI:10.1021/jacs.9b13818
日期:2020.4.8
Oxidative transpositions of bicyclic cyclopentenones mediated by selenium dioxide (SeO2) are disclosed. Treatment of Pauson-Khand reaction (PKR) products with SeO2 in the presence or absence of water furnishes di- and trioxidized cyclopentenones, respectively. Mechanistic investigations reveal multiple competing oxidation pathways that depend on substrate identity and water concentration. Functionalization
We have established that a cationic rhodium(I)-dppf complex catalyzes isomerizations of allyl propargyl ethers to allenic aldehydes in good yields from room temperature to 40 degrees C. On the other hand, carbonyl migration reactions from allenic aldehydes further proceed to give dienals in good yields at 80 degrees C.