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A convenient and efficient synthetic method for the construction of 2,3-disubstituted pyrrolamides in moderate to good yields is established. The in situ generated water significantly accelerates the reaction rate. A possible mechanism involving the cascade ring-opening and thermal-induced rearrangement to produce the five-membered ring is proposed. [ABSTRACT FROM AUTHOR]

In this paper, a novel Rh(I)-catalyzed Pauson–Khand-type[3 2 1] cycloaddition reaction of ene-vinylidenecyclopropanes(Ene-VDCPs) and carbon monoxide (CO) has been developed to furnisha series of aza- and oxa-bicyclic compounds in moderate to good yieldsin a highly regio- and diastereoselective manner, which provides analternative and efficient synthetic approach for the access of bicycliccyclohexanone frameworks. The substrate scope and limitations anda plausible mechanism are discussed. [ABSTRACT FROM AUTHOR]

An efficient diastereo- and enantioselectiveMannich-type/cyclizationcascade reaction of α-substituted isocyanoacetates and cyclictrifluoromethyl ketimines cooperatively catalyzed by cinchonaalkaloid-derived multi-hydrogen-bonding donor squaramide and AgOAchas been investigated, affording the optically active trifluoromethyl-substitutedtetrahydroimidazo[1,5-c]quinazoline derivatives inexcellent yields (up to 99%) and good to excellent stereoselectivities(up to >15:1 dr, up to 98% ee) under mild conditions. [ABSTRACT FROM AUTHOR]

A novelasymmetric formal [3+2] cycloaddition of vinyl cyclopropanes and isatinsin the presence of Pd2(dba)3and the chiralimidazoline-phosphine ligand (aS,R,R)-L3has been developed, affording the corresponding highly functionalizedoxindole-fused spirotetrahydrofuran frameworks in good yields alongwith good diastereo- and high enantioselectivities under mild conditions. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed asymmetric formal [3+2] cycloadditionof vinyl cyclopropanes and β,γ-unsaturated α-ketoesters proceeded smoothly in the presence of chiral imidazoline–phosphineligands to give the corresponding highly functionalized cyclopentanesin good yields along with high diastereo- and enantioselectivitiesunder mild conditions. [ABSTRACT FROM AUTHOR]