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A simple, broad‐scope rhodium(I)/chiral diene catalytic system for challenging asymmetric intramolecular cyclopropanation of various tri‐substituted allylic diazoacetates was successfully developed. The low coordination state RhI‐complex exhibits an extraordinarily high degree of tolerance to the variation in the extent of substitution of the allyl double bond, thus allowing the efficient construction of a wide range of penta‐substituted, fused‐ring cyclopropanes bearing three contiguous stereogenic centers, including two quaternary carbon stereocenters, in a highly enantioselective manner with ease at catalyst loading as low as 0.1 mol %. The stereoinduction mode of this RhI‐carbene‐directed asymmetric intramolecular cyclopropanation was investigated by DFT calculations, indicating that π‐π stacking interactions between the aromatic rings of chiral diene ligand and diazo substrate play a key role in the control of the reaction enantioselectivity. [ABSTRACT FROM AUTHOR]

Abstract: A highly efficient phosphine‐catalyzed [4+2] annulation of electron‐deficient diene and alkyl vinyl ketone was developed for the first time, which provides an easy access to functionalized cyclohexenes. This method has the advantages of mild reaction conditions, widely functional group tolerance, high yields and transition metal free. [ABSTRACT FROM AUTHOR]

A novel phosphine-catalyzed, highly enantioselective umpolung addition of trifluoromethyl ketimines to Morita-Baylis-Hillman carbonates was developed and it provides facile access to optically active trifluoromethyl amines with a chiral tertiary stereocenter under mild reaction conditions. The salient features of this reaction include general substrate scope, mild reaction conditions, good yields, high enantioselectivity, ease of scale-up to gram scale, and further transformations of the products. [ABSTRACT FROM AUTHOR]