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Chiral tertiary phosphines are versatile Lewis base catalysts capable of promoting a wide range of asymmetric reactions. In particular, the recent designed chiral phosphines based on the concept of bi‐/multifunctionality have been demonstrated to be effective catalysts for many types of asymmetric reactions such as (aza)‐MBH reaction/RC reaction, cycloaddition reaction, domino reaction, nucleophilic addition reaction, etc. This review summarizes the recent advances in this field and highlights the selected significant achievements. [ABSTRACT FROM AUTHOR]

A dimerization and cyclization cascade reaction of 2‐sulfonaminoacrylates catalyzed by K2CO3 provides dihydro‐2‐oxopyrrole (DPO) derivatives. This straightforward and atom‐economic transformation features a simple experimental operation with easily available starting materials, a broad substrate scope as well as good functional group tolerance. The desired DPO building blocks are obtained in moderate to good yields. [ABSTRACT FROM AUTHOR]

A phosphine‐catalyzed intermolecular annulation reaction of functionalized ortho‐aminoacetophenones with alkynones has been disclosed in this paper. A variety of 2‐alkynylquinolines and benzo‐fused indolizine were selectively afforded in moderate to good yields at different reaction temperatures and with different phosphine catalysts via the in situ generated zwitterionic intermediate derived from alkynone and phosphine. [ABSTRACT FROM AUTHOR]

A catalyst‐free self‐catalyzed [3+2] cycloaddition reaction of 3‐isothiocyanato oxindoles with vinylpyridines has been established, affording the desired products in high yields (up to 97 %) with moderate to good diastereoselectivities (up to 11:1) under mild conditions. The reaction mechanism has been investigated by control experiments, DFT calculations of pKa values and the kinetic studies, revealing that this reaction featured the mutual activation between 3‐isothiocyanato oxindole and vinylpyridine to generate the reactive species. Furthermore, these products could be easily transformed into the corresponding methylated and hydroxylated products under basic conditions. [ABSTRACT FROM AUTHOR]

An efficient temperature‐dependent organocatalyzed asymmetric formal [3+2] cycloaddition reaction of α‐substituted isocyanoacetates to β‐trifluoromethylated enones by cinchona alkaloid‐derived squaramide has been investigated, affording the optically active trifluoromethylated 2‐pyrrolines in excellent yields (up to 98 %) and high stereoselectivities (>20:1 dr, up to >99 % ee) under mild conditions. [ABSTRACT FROM AUTHOR]

Abstract: A catalyst‐free self‐catalyzed [3+2] cycloaddition reaction of isatin‐derived α‐(trifluoromethyl)imines with vinylpyridines is reported. The reaction offers a straightforward and atom‐economical procedure for the preparation of a series of 5′‐trifluoromethyl‐spiro[pyrrolidin‐3,2′‐oxindoles] in excellent yields and diastereoselectivities. The reaction mechanism has been investigated by control experiments, DFT calculation of pKa values and the kinetic profiles, revealing that this reaction featured the mutual activation between isatin‐derived α‐(trifluoromethyl)imines and vinylpyridine to generate the reactive species. [ABSTRACT FROM AUTHOR]

The highly efficient organocatalytic enantioselective [3+2] cyclization of 3-isothiocyanato oxindoles with trifluoromethylated 2-butenedioic acid diesters for the synthesis of spirooxindoles possessing a CF3-containing quaternary carbon stereocenter was explored. An enantiodivergent approach for the synthesis of spirooxindoles by regulation of the temperature was demonstrated at different temperatures. The outcome of the reaction featured high diastereo- and enantioselectivities. Several interesting enantioenriched spirooxindole derivatives bearing a trifluoromethyl quaternary carbon stereocenter were synthesized from the products of this reaction. [ABSTRACT FROM AUTHOR]

Catalytic asymmetric [3+2] cycloadditions of C,N-cyclic azomethine imines with δ-substituted allenoates have been developed in the presence of ( S)-Me-f-KetalPhos, affording functionalized tetrahydroquinoline frameworks in good yields with high diastereo- and good enantioselectivities under mild condition. The substrate scope has been also examined. This is the first time that δ-substituted allenoates have been applied as a δ,γ-CC bond participated C2 synthon in asymmetric synthesis. [ABSTRACT FROM AUTHOR]

A highly regio- and stereoselective synthesis of bispirooxindoles by 1,3-dipolar cycloaddition of in situ generated azomethine ylides from isatin and proline to different electron-deficient alkenes has been developed. The synthesis affords the desired bispiro scaffold compounds in excellent yields with high regioselectivity under mild conditions. The stereochemistry was determined by single-crystal X-ray analysis. [ABSTRACT FROM AUTHOR]

A novel type of yne-vinylidenecyclopropanes (VDCPs) has been synthesized and applied in gold-catalyzed cycloisomerization reactions. It was found that these compounds can undergo an intramolecular cycloisomerization and perform as a three-carbon synthon for [3+2] cycloaddition under gold catalysis to give fused [4.3.0] and [5.3.0] bicyclic derivatives and VDCP rearranged products in moderated to good yields under mild conditions. The substrate scope of these novel transformations has been explored and plausible reaction mechanisms have been presented on the basis of deuterium labeling experiments and DFT calculations. [ABSTRACT FROM AUTHOR]

The catalytic asymmetric [3+2] cycloaddition of (3-isothiocyanato)oxindoles with azodicarboxylates has been explored in the presence of (DHQD)2PHAL. It affords spirooxindoles having two heterocycles at their C3′-position in excellent yields, with high enantioselectivities, and under mild conditions within 5 min. Moreover, another spirooxindole derived from the reaction of (3-isothiocyanato)oxindole with two molecules of azodicarboxylate could also be formed in excellent yields with the same high enantioselectivities under the standard conditions. [ABSTRACT FROM AUTHOR]