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. This journal is © the Partner Organisations 2014.

Venkitasamy Kesavan

Department Of Biotechnology

V. Pratap Reddy Gajulapalli

Poopathy Vinayagam

Selective catalytic reduction

Thioureas

3-HYDROXYOXINDOLES

Bi-functional

Enantioselective

Enantioselective synthesis

l-Proline

Organocatalytic

Enantioselectivity

Isatin

proline

thiourea

catalysis

chemistry

decarboxylation

methylation

Stereoisomerism

synthesis

Fulltext

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Organic and Biomolecular Chemistry

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. © Georg Thieme Verlag Stuttgart, New York.

Synthesis (Germany)

Construction of Polycyclic Fused Pyrrolidines with Three Contiguous Stereocenters via Michael Addition of Vinylmalononitriles to Nitrostyrenes Using l -Proline-Derived Thiourea

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). © 2016 The Royal Society of Chemistry.

Chemical Communications

An efficient construction of: N, N -bicyclic pyrazolidinones comprising enaminonitriles via asymmetric [3+2] cycloaddition

Sequential vinylogous Michael addition-cyclization reactions of vinyl malononitriles with isatylidene malononitrile were accomplished using l-proline derived bifunctional thiourea. Cyclohexylidine malononitrile afforded exclusively the single diastereomer with good to excellent enantioselectivity (up to 99% ee) for diverse oxindole spirocyclohexene derivatives. Tetralone derived α,α-dicyano alkene was also employed to access spirocyclic oxindole scaffolds with an excellent level of stereoselectivity (up to 99% ee). © The Royal Society of Chemistry.

RSC Advances

Enantioselective assembly of functionalized carbocyclic spirooxindoles using an L-proline derived thiourea organocatalyst

Organocatalytic asymmetric decarboxylative cyanomethylation of isatins using l-proline derived bifunctional thiourea

Journal	Data powered by TypesetOrganic and Biomolecular Chemistry
Publisher	Data powered by TypesetRoyal Society of Chemistry
ISSN	14770520
Open Access	No