A novel Fe(II)/diaryl prolinol catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides with alkenes

Organic synthesis with the most abundant transition metal–iron: from rust to multitasking catalysts

The promising aspects of iron in synthetic chemistry are being explored for three-four decades as a green and eco-friendly alternative to late transition metals. This present review unveils these rich iron-chemistry towards different transformations.

Stereochemical diversity in pyrrolidine synthesis by catalytic asymmetric 1,3-dipolar cycloaddition of azomethine ylides

The pyrrolidine ring is a privileged structural motif in synthetic and medicinal chemisty. This review aims to highlight the high versatility of the catalytic asymmetric 1,3-dipolar cycloaddition of azomethine ylides for access to different types of stereochemical patterns in enantioselective pyrrolidine synthesis. Special attention will be paid to stereodivergent procedures giving rise to different stereoisomers from the same starting materials.

Iodine/K2CO3-catalyzed synthesis of multisubstituted pyrrolidine-2-carboxylates via a one-pot reaction between an araldehyde, an amino acid ester, and a chalcone

A series of more than 20 multisubstituted pyrrolidine-2-carboxylates were synthesized via a one-pot cycloaddition of an araldehyde, an amino acid ester, and a chalcone catalyzed by I2/K2CO3 in tetrahydrofuran at 80 °C. The advantages of this method are readily available starting materials, mild conditions, and simple operation, and it is metal free and yields are good to excellent.

Highly diastereoselective C → N acyl rearrangement in polysubstituted pyrrolidine 2,2-dicarboxylates. Stereocontrolled synthesis of densely functionalized prolines

A fully diastereoselective C–N acyl transfer reaction operates in enantiopure densely substituted pyrrolidine 2,2-dicarboxylates.

How the mechanism of a [3 + 2] cycloaddition reaction involving a stabilized N-lithiated azomethine ylide toward a π-deficient alkene is changed to stepwise by solvent polarity? What is the origin of its regio- and endo stereospecificity? A DFT study using NBO, QTAIM, and NCI analyses

The regio- and endo stereospecific 32CA reaction of the stabilized N-lithiated azomethine ylide 2 toward the π-deficient alkene 3in THF occurs to afford cycloadduct 6via a stepwise mechanism, passing through the zwitterionic intermediate 4.