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• 30169-43-8 3-methyl-3-(phenylmethyl)-2,4-pentandione 
• 765-69-5 2-Methylcyclopentane-1,3-dione 
• 100-39-0 benzyl bromide 
• 17082-61-0 1,2-bis(trimethylsiloxy)cyclobutene 
• 103-79-7 1-phenyl-acetone 
• 10432-39-0 2-(1-phenylpropylidene)malononitrile 
• 1383003-35-7 2-benzyl-2-methylcyclopent-4-ene-1,3-dione 
• 108264-59-1 Diethyl 2-benzyl-2-methyl-3-oxohexanedioate 
• 123120-11-6 ethyl (Z)-2-(5-oxotetrahydrofuran-2-ylidene)propionate 
• 100-44-7 benzyl chloride 
• 108264-64-8 3-Benzyl-3-methyl-2,4-dioxo-cyclopentanecarboxylic acid ethyl ester 

Relevant academic research and scientific papers

Desymmetric enantioselective reduction of cyclic 1,3-diketones catalyzed by a recyclable p-chiral phosphinamide organocatalyst

The P-stereogenic phosphinamides are a structurally novel skeletal class which has not been investigated as chiral organocatalysts. However, chiral cyclic 3-hydroxy ketones are widely used as building blocks in the synthesis of natural products and bioactive compounds. However, general and practical methods for the synthesis of such chiral compounds remain underdeveloped. Herein, we demonstrate that the P-stereogenic phosphinamides are powerful organocatalysts for the desymmetric enantioselective reduction of cyclic 1,3-diketones, providing a useful method for the synthesis of chiral cyclic 3-hydroxy ketones. The protocol displays a broad substrate scope that is amenable to a series of cyclic 2,2-disubstituted five- and six-membered 1,3-diketones. The chiral cyclic 3-hydroxy ketone products bearing an all-carbon chiral quaternary center could be obtained with high enantioselectivities (up to 98% ee) and diastereoselectivities (up to 99:1 dr). Most importantly, the reactions could be practically performed on the gram scale and the catalysts could be reused without compromising the catalytic efficiency. Mechanistic studies revealed that an intermediate formed from P-stereogenic phosphinamide and catecholborane is the real catalytically active species. The results disclosed herein bode well for designing and developing other reactions using P-stereogenic phosphinamides as new organocatalysts.

Chiral Phosphoric Acid Catalyzed Desymmetrization of Cyclopentendiones via Friedel–Crafts Conjugate Addition of Indolizines

An organocatalytic highly diastero- and enantioselective Friedel–Crafts conjugate addition of indolizines to prochiral cyclopentenediones has been successfully developed. This desymmetric transformation provides a direct access to the desired indolizine-substituted cyclopentanediones in yields of 62–91% and excellent stereoselectivities. The utility of the approach was demonstrated by diverse late-stage functionalizations through reduction or oxidation. Importantly, the direct sp2 C–H functionalization with nitromethane in one-pot process resulted in the indolizine-linked axially chiral styrene bearing a remote chiral center.

Stereoselective Reduction of Prochiral Cyclic 1,3-Diketones Using Different Biocatalysts

We have developed biocatalytic methods for the stereoselective reduction of cyclic prochiral 1,3-diketones for the production of optically active β-hydroxyketones and/or 1,3-diols. The recombinant ketoreductase KRED1-Pglu (formulated as purified catalyst)

Desymmetrization of meso-bisphosphates via rhodium catalyzed asymmetric allylic arylation

The desymmetrization of meso-compounds allows for the unmasking of previously installed stereogenic centers, and quaternary centers are of special interest as they are frequently challenging to form with control in synthesis. Here, we report the desymmetr

Access to All-Carbon Spirocycles through a Carbene and Thiourea Cocatalytic Desymmetrization Cascade Reaction

A new catalytic approach for rapid asymmetric access to spirocycles is disclosed. The reaction involves a carbene- and thiourea-cocatalyzed desymmetrization process with the simultaneous installation of a spirocyclic core. The use of a thiourea cocatalyst

Vinylogous Annulation Cascade Toward Stereoselective Synthesis of Highly Functionalized Indanone Derivatives

A base promoted vinylogous annulation cascade of alkylidene malononitriles with cyclopentene-1,3-diones with a subsequent reduction sequence has been devised to furnish densely functionalized 3-hydroxyindanone scaffolds in high yields with excellent diastereoselectivity. Unlike preceding approaches that account for the formation of the pentanoid ring, this strategy features construction of the aromatic ring. The protocol is scalable, displays very broad substrates scope including late-stage functionalization of bioactive estrone, applicable to activated coumarin system, and is suitable to access an indenoquinoline derivative. (Figure presented.).

Silver-Catalyzed Asymmetric Desymmetrization of Cyclopentenediones via [3 + 2] Cycloaddition with α-Substituted Isocyanoacetates

A highly selective and practical asymmetric Ag(I) catalyst system has been developed for the [3 + 2] cycloaddition reactions between isocyanoacetates and cyclopentenediones. The current Ag(I) catalyst system tolerates moisture and air and readily utilizes class III solvents such as EtOAc and acetone. The development of on demand generation of an active chiral catalyst in the presence of isocyanides paves a way to the efficient asymmetric preparation of bicyclic pyrrolidines with four stereogenic centers, including two quaternary centers in 80-97% ee.

Synthesis of new spiro pyrrole/pyrrolizine/thiazole derivatives via (3+2) cycloaddition reactions

A new series of spiro pyrrole/pyrrolizine/thiazole compounds have been synthesized using (3+2) dipolar cycloaddition via three-component condensation reactions of ninhydrin and α-amino acids with different dipolarophiles such as maleimide, malic anhydride

Desymmetrization of Cyclopentenediones via Organocatalytic Cross-Dehydrogenative Coupling

An enantioselective synthesis of cyclopentenediones bearing a pyrazole unit has been achieved through an organocatalytic Michael addition/oxidation process. This desymmetrization reaction led to the desired pyrazole-cyclopentenediones with high yield and

Silver(I)-Ferrophox Catalyzed Enantioselective Desymmetrization of Cyclopentenedione: Synthesis of Highly Substituted Bicyclic Pyrrolidines

A highly enantioselective desymmetrization of prochiral cyclopentene-1,3-dione via [3 + 2] cycloaddition of azomethine ylide using a silver(I)-ferrophox complex has been demonstrated. The method has been utilized in the synthesis of highly functionalized enantioenriched 5,5-fused bicyclic pyrrolidine derivatives under mild reaction conditions.