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First asymmetric decarboxylative cyanomethylation of isatins is reported herewith using bifunctional thiourea derived from l-proline in good yields and enantioselectivities. This strategy enables the construction of various 3-cyanomethylene substituted 3-hydroxyoxindoles in enantioselective manner. Enantioselective synthesis of CPC-1 alkaloid has been accomplished in fewer steps.

Organocatalytic Friedel‐Crafts aminoalkylation reaction is demonstrated in this study for the construction of biologically important hybrid molecular architectures of carbazole containing 3‐amino oxindoles using bifunctional cinchonidine derived thiourea organocatalyst. The Friedel‐Crafts functionalization of 4‐hydroxy carbazole with isatin derived ketimines well performed with a wide range of substrates resulted in excellent yields (up to 95 %) and enantioselectivities (up to 99 % ee) of the desired products. A minimal catalyst loading (0.5 mol%) was utilized at ambient temperatures under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Enantioselective construction of bioinspired coumarin and oxindole hybrid structures always enduring challenges in organic chemistry due to the generation of asymmetric quaternary/spiro center at the C3 position of oxindole. Herein, we demonstrated a facile enantioselective synthesis of highly functionalized 3,3'‐disubstituted oxindole derivatives containing 3‐acetyl coumarins and pyranocoumarin fused spirooxindoles using L‐proline derived bifunctional thiourea organocatalyst through Aldol reaction and Michael addition/cyclization. The L‐proline derived thiourea catalyst well performed with broad substrate scope to produce desired products in very good yields (up to 95 %) and excellent enantioselectivities (up to 99 % ee). [ABSTRACT FROM AUTHOR]

The first thiourea catalysed asymmetric [3+2] cycloaddition reaction between azomethine imines and malanonitriles was developed. Using this novel synthetic strategy, hybrid molecules containing N,N-bicyclic pyrazolidinones fused with enaminonitriles were synthesized in good yields with excellent enantioselectivities (up to 98% ee). [ABSTRACT FROM AUTHOR]

The catalytic efficiency of a bifunctional chiral thiourea derived from L-proline was evaluated in the asymmetric direct vinylogous Michael reaction of α,α-dicyanoolefins to β-nitrostyrenes with an electron- releasing or electron-withdrawing substituent in various positions. The corresponding adducts were isolated in good yields, with excellent diastereo- (>99%) and enantioselectivity (up to 95%). The Michael adducts were further functionalized to achieve the synthesis of polycyclic fused pyrrolidines with three contiguous stereocenters in good enantioselectivities. [ABSTRACT FROM AUTHOR]

The new proline-derived squaramide organocatalyst is shown to exhibit higher efficiency than known thiourea and squaramide ligands. [ABSTRACT FROM AUTHOR]

Abstract: A new class of bifunctional tertiary amine thiourea was synthesized from l-proline. The reported thiourea is amenable to steric and electronic modifications at the stereogenic center bearing a thiourea moiety. Excellent enantioselectivity was obtained in the Michael addition of 2,4-pentanedione to various nitro olefins using the new organocatalyst. The construction of contiguous stereocenters via the Michael reaction of substituted 1,3-dicarbonyls to nitro olefins was also carried out with very good yield, enantioselectivity, and diastereoselectivity. [Copyright &y& Elsevier]

Multifunctional spirooxindole scaffolds are synthesized by enantioselective multi‐component reactions involving sequential vinylogous Michael addition and cyclization. [ABSTRACT FROM AUTHOR]

The natural product CPC-1 (VI) is prepared by the presented approach as key step. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Organocatalytic Construction of Spirooxindole Naphthoquinones Through Michael/Hemiketalization Using-Proline Derived Bifunctional Thiourea" by V. Pratap Reddy Gajulapalli and others, published in the "RSC Advance" in 2016.