1370352-23-0

Upstream product

• 459-57-4 4-fluorobenzaldehyde 
• 28144-70-9 anthranilic acid amide 
• 359605-44-0 2-(4-fluorophenyl)-2,3-dihydroquinazolin-4(1H)-one 
• 66822-17-1 4-(1,3-dioxolan-2-yl)fluorobenzene 
• 32691-93-3 α,α-dimethoxy-4-fluorotoluene 
• 39769-08-9 N-(4-fluorobenzylidene)-4-methoxyaniline 

Relevant academic research and scientific papers

Enantioselective PCCP Br?nsted acid-catalyzed aminalization of aldehydes

Here we present an enantioselective aminalization of aldehydes catalyzed by Br?nsted acids based on pentacarboxycyclopentadienes (PCCPs). The cyclization reaction using readily available anthranilamides as building blocks provides access to valuable 2,3-dihydroquinazolinones containing one stereogenic carbon center with good enantioselectivity (ee up to 80%) and excellent yields (up to 97%).

Homochiral Dodecanuclear Lanthanide "cage in Cage" for Enantioselective Separation

It is extremely difficult to anticipate the structure and the stereochemistry of a complex, particularly when the ligand is flexible and the metal node adopts diverse coordination numbers. When trivalent lanthanides (LnIII) and enantiopure amino acid ligands are utilized as building blocks, self-assembly sometimes yields rare chiral polynuclear structures. In this study, an enantiopure carboxyl-functionalized amino acid-based ligand with C3 symmetry reacts with lanthanum cations to give a homochiral porous coordination cage, (Δ/λ)12-PCC-57. The dodecanuclear lanthanide cage has an unprecedented octahedral "cage-in-cage"framework. During the self-assembly, the chirality is transferred from the enantiopure ligand and fixed by the binuclear lanthanide cluster to give 12 metal centers that have either Δor λ homochiral stereochemistry. The cage exhibits excellent enantioselective separation of racemic alcohols, 2,3-dihydroquinazolinones, and multiple commercially available drugs. This finding exhibits a rare example of a multinuclear lanthanide complex with a dual-walled topology and homochirality. The highly ordered self-assembly and self-sorting of flexible amino acids and lanthanides shed light on the chiral transformation between different complicated artificial systems that mimic natural enzymes.

C3 The symmetry contains a chiral ligand H3L of an amide bond. Preparation method and application

The invention discloses C. 3 Chiral ligand H with symmetric amide bond3 L Relates to the technical field of material chemistry and chiral chemistry. The invention further provides the chiral ligand H. 3 L Preparation method and application thereof. The present invention has the advantage that the chiral ligand H of the present invention is a chiral ligand. 3 The L has a higher C. 3 The symmetric and flexible amide group enables coordination of the lanthanide metal ions with high coordination number and high oxygen affinity to be assembled into a novel structure-structure lanthanide metal chiral porous coordination cage. Moreover, the abundant chiral amide groups and amino acid residues on the ligand framework can be directly introduced into the synthesized lanthanide metal chiral porous coordination cage, thereby being beneficial to generating multiple chiral recognition sites and unique chiral microenvironments which mimic the biological enzyme binding pocket and further realize the purpose of high enantioselectivity separation of a series of chiral small molecule compounds.

Highly Stable Zr(IV)-Based Metal-Organic Frameworks with Chiral Phosphoric Acids for Catalytic Asymmetric Tandem Reactions

Heterogeneous Br?nsted acid catalysts featuring high porosity, crystallinity, and stability have been of great interest for both fundamental studies and practical applications, but synthetically, they still face a formidable challenge. Here, we illustrated a ligand design strategy for directly installing chiral phosphoric acid catalysts into highly stable Zr-MOFs by sterically protecting them from coordinating with metal ions. A pair of chiral porous Zr(IV)-MOFs with the framework formula [Zr6O4(OH)8(H2O)4(L)2] were prepared from enantiopure 4,4′,6,6′-tetra(benzoate) and -tetra(2-naphthoate) ligands of 1,1′-spirobiindane-7,7′-phosphoric acid. They share the same topological structure but differ in channel sizes, and both of them demonstrate excellent tolerance toward water, acid and base. Significantly enhanced Br?nsted acidity was observed for the phosphoric acids that are uniformly distributed within the frameworks in comparison with the nonimmobilized acids. This not only facilitates the catalysis of asymmetric two-component tandem acetalization, Friedel-Crafts, and iso-Pictet-Spengler reactions but also promotes the catalysis of asymmetric three-component tandem deacetalization-acetalization and Friedel-Crafts reactions benefiting from the synergy with exposed Lewis acidic Zr(IV) sites. The enantioselectivities are comparable or favorable compared to those obtained from the corresponding homogeneous systems. The features of high reactivity, selectivity, stability, and recyclability for Zr(IV)-MOFs make them hold promise as a new type of heterogeneous acid catalyst for the eco-friendly synthesis of fine chemicals.

Boosting Enantioselectivity of Chiral Organocatalysts with Ultrathin Two-Dimensional Metal-Organic Framework Nanosheets

The development of methodologies for inducing and tailoring enantioselectivities of catalysts is an important issue in asymmetric catalysis. In this work, we demonstrate for the first time that chiral molecular catalysts can be boosted from completely nonselective to highly enantioselective when installed in nanostructured metal-organic frameworks (MOFs). Exfoliation of layered crystals is one of the most direct synthetic routes to unltrathin nanosheets, but its use in MOFs is limited by the availability of layered MOFs. We illustrate that layered MOFs can be designed using ligand-capped metal clusters and angular organic linkers. This leads to the synthesis of two three-dimensional (3D) layered porous MOFs from Zn4-p-tert-butylsulfonyl calix[4]arene and chiral angular 1,1′-binaphthol/-biphenol dicarboxylic acids, which can be ultrasonic exfoliated into one- and two-layer nanosheets. The obtained MOF materials are efficient catalysts for asymmetric cascade condensation and cyclization of 2-aminobenzamide and aldehydes to produce 2,3-dihyroquinazolinones. While both binaphthol and biphenol display no enantioselectivity, restriction of their freedom in the MOFs leads to 56-90% and 46-72% ee, respectively, which are increased to 72-94% and 64-82% ee after exposure to external surfaces of the flexible nanosheets. Moreover, the MOF crystals and nanosheets exhibit highly sensitive fluorescent enhancement in the presence of chiral amino alcohols with enantioselectivity factors being, respectively, increased up to 1.4 and 2.3 times of the values of the diols, allowing them to be utilized in chiral sensing. Therefore, the observed enantioselectivities increase in the order organocatalyst MOF crystals MOF nanosheets in both catalysis and sensing. This work not only provides a strategy to make 3D layered MOFs and their untrathin nanosheets but also paves the way to utilize nanostructured MOFs to manipulate enantioselectivities of molecular catalysts.

Enantioselective synthesis of dihydroquinazolinone derivatives catalyzed by a chiral organocatalyst

The asymmetric condensation/amine addition cascade sequence of 2-aminobenzamide and aldehydes, catalyzed by a novel chiral organocatalyst, was realized. The organocatalyst was found to be very effective and highly enantioselective for such cascade reactions at room temperature, affording 2,3-dihydroquinazolinones in excellent yields (up to 99%) with enantiomeric excesses of up to 97%. The best level of stereocontrol was obtained for aromatic/aliphatic aldehydes with ortho, para or meta substituents.

Investigation of the enantioselective synthesis of 2,3- Dihydroquinazolinones Using Sc(III)- Inda -pybox

Derivatives of 2,3-dihydroquinazolinones (2,3-DHQZs) are prized for their prevalent pharmaceutical applications. Although there are potential applications, methods available for the enantioselective synthesis of these valuable compounds are scarce, since the chiral aminal center is prone to racemization. We have overcome the difficulties in the catalytic enantioselective synthesis of 2,3-DHQZs using Sc(III)-inda-pybox as a catalyst, in a process with a broad substrate scope. Georg Thieme Verlag Stuttgart. New York.

Highly enantioselective synthesis of 2,3-dihydroquinazolinones through intramolecular amidation of imines

Enantioselective synthesis of 2,3-dihydroquinazolinones (DHQZs) was accomplished using readily available Sc(III)-inda-pybox as the catalyst. This is the first report on the metal catalyzed asymmetric intramolecular amidation of imines to synthesize DHQZs.

Catalytic asymmetric synthesis of dihydroquinazolinones from imines and 2-aminobenzamides

An unprecedented catalytic asymmetric synthesis of aminal-containing heterocyclic compounds has been developed from imines and tethered nitrogen/nitrogen nucleophiles. In the presence of 10mol% of a commercially available chiral phosphoric acid, a range of aromatic, α,β- unsaturated, and aliphatic imines react with 2-aminobenzamides to give dihydroquinazolinones in good to excellent yields and ee. The enantioselectivity is significantly affected by the imine N-substituent through non-bonding interactions with the chiral phosphoric acid and the 2-aminobenzamide. Copyright