Asymmetric Hetero Diels-Alder Reaction Research Articles

Asymmetric Hetero-Diels–Alder Reaction of 4-Phenyl-1,2,4-triazole-3,5-dione with 2,4-Dienyl Carboxylic Acids

AbstractThe enantioselective hetero-Diels–Alder reaction of the cyclic azo compound 4-phenyl-1,2,4-triazole-3,5-dione with 2,4-dienyl carboxylic acids was performed using tartaric acid ester as the chiral auxiliary. The corresponding cycloadducts were obtained with enantioselectivities of up to 76% ee. The cis-carboxylic acid produced could be converted into the corresponding cis- and trans-methyl esters by varying the reaction conditions.

Nickel-Catalyzed Regiodivergent Asymmetric Cycloadditions of α,β-Unsaturated Carbonyl Compounds

Nickel-Catalyzed Regiodivergent Asymmetric Cycloadditions of α,β-Unsaturated Carbonyl Compounds

Biomimetic approach to the catalytic enantioselective synthesis of tetracyclic isochroman

Polyketide oligomers containing the structure of tetracyclic isochroman comprise a large class of natural products with diverse activity. However, a general and stereoselective method towards the rapid construction of this structure remains challenging due to the inherent instability and complex stereochemistry of polyketide. By mimicking the biosynthetic pathway of this structurally diverse set of natural products, we herein develop an asymmetric hetero-Diels–Alder reaction of in-situ generated isochromene and ortho-quinonemethide. A broad range of tetracyclic isochroman frameworks are prepared in good yields and excellent stereoinduction (up to 95% ee) from readily available α-propargyl benzyl alcohols and 2-(hydroxylmethyl) phenols under mild conditions. This direct enantioselective cascade reaction is achieved by a Au(I)/chiral Sc(III) bimetallic catalytic system. Experimental studies indicate that the key hetero-Diels-Alder reaction involves a stepwise pathway, and the steric hindrance between in-situ generated isochromene and t-Bu group of Sc(III)/N,N’-dioxide complex is responsible for the enantioselectivity in the hetero-Diels–Alder reaction step.

Simple amino silyl ether organocatalyst for asymmetric hetero Diels–Alder reaction of isatins with enones

New two catalysts component system comprising of a primary β-amino silyl ethers as an organocatalyst and N-protected amino acids as a co-catalyst put together worked as an efficient organocatalyst system in the hetero Diels-Alder reaction of isatins with enones affording the chiral spirooxindole-tetrahydropyranones in good chemical yields and stereoselectivities (up to 94%, up to dr 78:22., up to 85% ee).

Ni-Catalyzed asymmetric hetero-Diels–Alder reactions of conjugated vinyl azides: synthesis of chiral azido polycycles

We report herein an efficient Ni(ii)/Feng ligand-catalyzed asymmetric hetero-Diels–Alder reaction between conjugated vinyl azides with carbonyl groups, providing a synthesis of complicated chiral azido polycycles in high yields and excellent enantioselectivities.

Chiral paddle-wheel diruthenium complexes for asymmetric catalysis

The development of robust and reactive chiral catalysts is a fundamental aim in asymmetric catalysis, and crucial for providing efficient methods for synthesizing chiral molecules. Chiral paddle-wheel bimetallic complexes provide a highly tunable chiral environment in rhodium-catalysed asymmetric carbene/nitrene transfer reactions and Lewis acid-catalysed reactions. Chiral paddle-wheel complexes having other transition metals as the reactive metal centre, however, have not yet been identified in asymmetric catalysis. Here, we report the synthesis, structures and high catalytic performances of chiral paddle-wheel diruthenium complexes. The cationic chiral diruthenium complex [Ru2((S)-BPTPI)4]+ exhibited remarkable reactivity as a Lewis acid catalyst for asymmetric hetero-Diels–Alder reactions, achieving a turnover number of up to 1,880,000 with high enantioselectivity (>90% e.e.). The chiral diruthenium complexes also exhibited good reactivity and high enantioselectivity in C–H amination and cyclopropanation reactions under oxidizing conditions, indicating their high tolerance towards oxidation. Our results reveal the chiral paddle-wheel diruthenium scaffold as a promising platform for asymmetric catalysis. The development of chiral catalysts is of fundamental importance in asymmetric catalysis. Now, chiral paddle-wheel diruthenium complexes are reported that are stable under oxidizing conditions and effective in asymmetric C–C and C–N bond-forming reactions with turnover numbers of up to 1,880,000.

Simple organocatalyst component system for asymmetric hetero Diels-Alder reaction of isatins with enones.

A simple two catalyst component system consisting of primary β-amino alcohols as a catalyst and amino acids as a co-catalyst put together works as an efficient organocatalyst system in the hetero Diels–Alder reaction of isatins with enones to afford the chiral spirooxindole–tetrahydropyranones in good chemical yields and stereoselectivities (up to 86%, up to 85 : 15 dr., up to 95% ee).

Enantiopure (P)- and (M)-3,14-bis(o-hydroxyaryl)tetrahydrobenzo[5]helicenediols and their helicene analogues: Synthesis, amplified circularly polarized luminescence and catalytic activity in asymmetric hetero-Diels–Alder reactions

Three pairs of enantiopure (P)- and (M)-3,14-bis(o-hydroxyaryl)tetrahydrobenzo[5]helicenediols (ArOH-H[5]HOLs), and enantiomers (P)- and (M)-3,14-bis(o-hydroxyphenyl)benzo[5]helicene-diols (PhOH-[5]HOLs) were designed and synthesized. It was found that compared with ArOH-H[5]HOLs, PhOH-[5]HOLs not only showed obvious red-shifts in both absorption and emission spectra, but also exhibited more intense CPL with amplified glum, which might be attributed to the more rigid structure of PhOH-[5]HOLs. However, rigid PhOH-[5]HOLs was less effective in the catalytic asymmetric hetero-Diels–Alder (HAD) reactions than those of ArOH-H[5]HOLs with the flexible tetrahydro[5]helicene backbone that could adjust conformation to suit the substrates. Therefore, the helical chirality amplification and chirality transfer could be efficiently achieved by adjusting the rigid and flexible structures of helical molecules, which might provide a useful strategy to optimize the structure of helicence derivatives for their applications in chiroptical materials and asymmetric catalysis.

Total Synthesis of Divergolides E and H.

This manuscript describes the first total syntheses of divergolides E and H. The route employs a telescoped hetero-Diels-Alder and oxidative carbon-hydrogen bond cleavage as an entry into the central bridged bicyclic acetal unit. Additional key steps of the highly convergent route include a desymmetrizing epoxidation, a chelation-controlled alkenylzinc addition, an amide formation between a hindered aniline and an acylating agent that is prone to ketene formation, and a challenging macrolactonization.

Catalytic asymmetric hetero-Diels-Alder reactions of enones with isatins to access functionalized spirooxindole tetrahydropyrans: scope, derivatization, and discovery of bioactives.

The development of concise methods for the synthesis of functionalized small molecules is important in the search for new bioactive molecules. To contribute to this, we have developed oxa-hetero-Diels-Alder reactions of enones with isatins catalyzed by amine-based catalyst systems. Various spirooxindole tetrahydropyranones were synthesized either in enantiomerically enriched forms or as racemic forms depending on the catalyst system. The reaction products were further transformed at the ketone carbonyl group and the indole nitrogen. Using these reactions, functionalized spirooxindole tetrahydropyran derivatives with functional groups in four directions in a three-dimensional space were concisely obtained. From these synthesized compounds, an inhibitor of human ion channel Nav1.7 with μM-level activity was identified, indicating that the developed reaction methods are useful for providing molecules for the discovery of new biofunctional molecules.

The copper(II) complex of an amino indanol derivative immobilized over chiral mesostructured cellular foam as a catalyst for the asymmetric hetero-Diels–Alder reaction

A new series of chiral mesostructured cellular foams (MCF) was prepared by doping sodium lactates in a sol–gel process. The copper complex of an amino indanol derivative was prepared and immobilized into MCF and used in order to catalyze the asymmetric hetero-Diels–Alder reaction. Characterizations revealed that doping of sodium lactates gave the MCF matrix different chiral configurations, and copper complex was covalently attached to MCF. MCF-supported copper complexes were efficient catalysts, the synergy between the copper complex and MCF did work on chiral induction, and the supported copper complex could be used for three times without degradation. This work prepared new chiral silica materials, and afforded a new system for the asymmetric hetero-Diels–Alder reaction.

Highly asymmetric hetero-Diels–Alder reaction using helical silica-supported Mn(III)-salen catalysts

Helical silica were prepared and functionalized by Mn(III)-salen complexes in order to catalyze asymmetric hetero-Diels–Alder reactions. Characterizations revealed doping of sodium lactate facilitated porosity, hydrolysis resistance and chiral configuration of silica matrix. Catalysis revealed the combination of Mn(III)-salen with helical silica had excellent chiral induction. Major product configuration was affected by temperature and solvent. Loading imidazolium ionic liquid as solvent improved both enantioselectivity and catalyst recycling.

ChemInform Abstract: Asymmetric Hetero‐Diels—Alder Reaction of Diazenes Catalyzed by Chiral Silver Phosphate: Water Participates in the Catalysis and Stereocontrol.

ChemInformVolume 46, Issue 19 Heterocyclic Compounds ChemInform Abstract: Asymmetric Hetero-Diels—Alder Reaction of Diazenes Catalyzed by Chiral Silver Phosphate: Water Participates in the Catalysis and Stereocontrol. Bin Liu, Bin Liu Dep. Chem., Univ. Sci. Technol. China, Hefei 230026, Peop. Rep. ChinaSearch for more papers by this authorTong-Yu Liu, Tong-Yu Liu Dep. Chem., Univ. Sci. Technol. China, Hefei 230026, Peop. Rep. ChinaSearch for more papers by this authorShi-Wei Luo, Shi-Wei Luo Dep. Chem., Univ. Sci. Technol. China, Hefei 230026, Peop. Rep. ChinaSearch for more papers by this authorLiu-Zhu Gong, Liu-Zhu Gong Dep. Chem., Univ. Sci. Technol. China, Hefei 230026, Peop. Rep. ChinaSearch for more papers by this author Bin Liu, Bin Liu Dep. Chem., Univ. Sci. Technol. China, Hefei 230026, Peop. Rep. ChinaSearch for more papers by this authorTong-Yu Liu, Tong-Yu Liu Dep. Chem., Univ. Sci. Technol. China, Hefei 230026, Peop. Rep. ChinaSearch for more papers by this authorShi-Wei Luo, Shi-Wei Luo Dep. Chem., Univ. Sci. Technol. China, Hefei 230026, Peop. Rep. ChinaSearch for more papers by this authorLiu-Zhu Gong, Liu-Zhu Gong Dep. Chem., Univ. Sci. Technol. China, Hefei 230026, Peop. Rep. ChinaSearch for more papers by this author First published: 23 April 2015 https://doi.org/10.1002/chin.201519221Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume46, Issue19May, 2015 RelatedInformation

Asymmetric Hetero-Diels–Alder Reaction

Asymmetric Hetero-Diels–Alder Reaction

Silica-based helical rod supporting guanosine compounds catalyzed asymmetric hetero-Diels–Alder reaction

A series of silica-based helical rods were prepared and functionalized for immobilization of guanosine compounds in catalytic asymmetric hetero-Diels–Alder reaction. Nitrogen physisorption, electron microscopy and amino acid adsorption revealed that helical rod has a hierarchical structure including morphology and internal channels, and doping of sodium lactate facilitates porosity and internal chirality of synthetic rods. Catalysis revealed that guanosine derivatives were catalytically active, combination of guanosine with L-sodium lactate-doped rod was more enantioselective than that with zero- or D-sodium lactate-doped samples, and recycling of supported Schiff-base-guanosine was stable during six cycles.

ChemInform Abstract: Total Synthesis of Aphadilactones A—D.

AbstractA mixture of four diastereoisomers is synthesized in 11 steps and 7% overall yield.

Asymmetric hetero-Diels-Alder reaction of diazenes catalyzed by chiral silver phosphate: water participates in the catalysis and stereocontrol.

The chiral silver phosphate was confirmed to efficiently catalyze a highly regio- and enantioselective hetero-Diels-Alder reaction of diazenes to furnish piperazine derivatives in high yields and excellent ee values. DFT calculations revealed that the water molecule participates in the catalysis by coordination to silver phosphate and also found that the hydroxy group of 1-hydroxy-2,3-hexadiene not only formed a hydrogen bond with the oxygen of phosphate but also coordinated to the Ag(I) to simultaneously stabilize the transition states and control the regioselectivity.

A catalytic asymmetric hetero-Diels-Alder reaction of olefinic azlactones and isatins: facile access to chiral spirooxindole dihydropyranones.

A catalytic asymmetric hetero-Diels-Alder (HDA) reaction has been achieved through hydrogen-bond directed γ-addition of olefinic azlactones to isatins. This methodology provides an efficient access to spirooxindole dihydropyranones in moderate to good yields and with excellent enantioselectivities.

ChemInform Abstract: Stereoselective Synthesis of the C3—C12 Subunit of Laulimalide.

Abstract A stereoselective synthesis of the C3–C12 subunit of the tumor growth inhibitors laulimalide is disclosed. The key steps of the synthesis include asymmetric alkylation using Oppolzer’s protocol and an asymmetric hetero-Diels–Alder reaction using Jacobsen’s catalyst. Substrate controlled diastereoselective Luche reduction followed by Ferrier type reactions are other key steps.

Total synthesis of GEX1Q1, assignment of C-5 stereoconfiguration and evaluation of spliceosome inhibitory activity.

An enantioselective total synthesis of GEX1Q1 has been accomplished in a convergent manner. The C-5 asymmetric center has now been assigned through synthesis. GEX1Q1 displayed slightly better spliceosome inhibitory activity over its C-5 epimer. The salient features of this synthesis include an asymmetric hetero-Diels–Alder reaction to construct the tetrahydropyran ring and a Suzuki cross-coupling to assemble the key segments.