28809-07-6

Upstream product

• 1117-71-1 methyl-4-bromo-2-butenoate 
• 90-02-8 salicylaldehyde 
• 1117-71-1 methyl 4-bromocrotonate 
• 89-95-2 2-methyl-benzyl alcohol 
• 88018-07-9 methyl (Z)-4-(2-formylphenyloxy)but-2-enoate 
• 77733-81-4 (2E)-4-<2-(3-Cyan-trans-3-phenyl-2-oxiranyl)phenoxy>-2-butensaeure-methylester 
• 56699-18-4 cis-4-bromo-2-butenoic acid methyl ester 
• 3052-50-4 monomethyl maleate 
• 925230-65-5 methyl (Z)-4-hydroxy-but-2-enoate 

Downstream Products

• 4591-16-6 diphenylfumaronitrile 
• 77733-81-4 (2E)-4-<2-(3-Cyan-cis-3-phenyl-2-oxiranyl)phenoxy>-2-butensaeure-methylester 
• 77733-81-4 (2E)-4-<2-(3-Cyan-trans-3-phenyl-2-oxiranyl)phenoxy>-2-butensaeure-methylester 
• 117316-29-7 methyl N-<2-(3-carbomethoxyprop-2-enyl)oxy>benzylidenealaninate 
• 160427-30-5 benzaldehyde oxime 
• 205942-35-4 (E)-4-{2-[(E)-Ethoxycarbonylmethylimino-methyl]-phenoxy}-but-2-enoic acid methyl ester 
• 117406-51-6 (2S,3S,3aS,9bS)-2,3-dimethyl-2-phenyl-1,2,3,3a,4,9b-hexahydrochromeno[4,3-b]pyrrole-2,3-dicarboxylate 

Relevant academic research and scientific papers

Post-Ugi Cascade Transformations for Accessing Diverse Chromenopyrrole Collections

Employing a build/couple/pair strategy, a serendipitous one-pot protocol for the diastereoselective construction of diverse collections of chromenopyrroles is described. This methodology features an unprecedented five-step cascade including azomethine ylide generation followed by in situ intramolecular [3 + 2]-cycloaddition. Furthermore, this protocol was extended to access enantiopure chromenopyrroles using amino acids as chiral auxiliary. Moreover, postpairing reactions were employed to increase the diversity and complexity of our pilot compound collections.

Enantio- and diastereoselective [3+2] cycloadditions of azomethine ylides with Ag(I)-phosphinooxazoline catalysts

Chiral Ag(I)-phosphinooxazoline (PHOX) complexes are efficient catalysts for [3+2] cycloadditions of azomethine ylides with α,β-unsaturated carboxylic esters. In intramolecular cycloadditions, virtually complete diastereocontrol and enantiomeric excesses of up to 99% have been observed. Georg Thieme Verlag Stuttgart.

SUBSTITUTED CHROMANES, ANALOGS THEREOF, AND METHODS OF USE AND SYNTHESIS

Disclosed are chromane compounds, analogs thereof, and methods of their synthesis and use. The compounds may be synthesized by methods involving reductive annulations of arylidene malonates with unsaturated electrophiles using photoredox/Lewis acid cooperative catalysis. The compounds may be formulated in a pharmaceutical composition for treating one of the aforementioned diseases or disorders.

Intramolecular Stereoselective Stetter Reaction Catalyzed by Benzaldehyde Lyase

The reliable design and prediction of enzyme promiscuity to access transformations not observed in nature remains a long-standing challenge. Herein, we present the first example of an intramolecular stereoselective Stetter reaction catalyzed by benzaldehyde lyase, guided by the rational structure screening of various ThDP-dependent enzymes using molecular dynamics (MD) simulations. After optimization, high productivity (up to 99 %) and stereoselectivity (up to 99:1 e.r.) for this novel enzyme function was achieved.

One-Pot Synthesis of Diverse Collections of Benzoxazepine and Indolopyrazine Fused to Heterocyclic Systems

The development of efficient and modular synthetic methods for the synthesis of diverse collection of privileged substructures needed for a drug design and discovery campaign is highly desirable. Benzoxazepine and indolopyrazine ring systems form the core structures of distinct members of biologically significant molecules. Several members of these families have gained attention due to their broad biological activities, which depend on the type of ring-fusion and peripheral substitution patterns. Despite the potential applications of these privileged substructures in drug discovery, efficient, atom-economic, and modular strategies for their access are underdeveloped. Herein, a one-step build/couple/pair strategy that uniquely allows access to diversely functionalized benzoxazepine and indolopyrazine scaffolds is described. The methodology features a one-pot combination of condensation, Mannich, oxidation, and aza-Michael addition reactions, employing a variety of functionalized anilines and aldehydes suitably poised with Micheal acceptor. Scandium triflate (Sc(OTf)3) in acetonitrile (ACN) was found to promote the construction of benzoxazepines scaffolds, while sodium metabisulfite (Na2S2O5) in aqueous EtOH rapidly enhanced the cascade reaction that led to diverse collections of indolopyrazine frameworks. These protocols represent modular, efficient, and atom-economic access of constrained benzoxazepine and indolopyrazine systems with more than 10 points of diversity and large substrate tolerance.

Synthesis of Chromen[4,3-b]pyrrolidines by Intramolecular 1,3-Dipolar Cycloadditions of Azomethine Ylides: An Experimental and Computational Assessment of the Origin of Stereocontrol

Azomethine ylides, generated from imine-derived O-cinnamyl or O-crotonyl salicylaldeyde and α-amino acids, undergo intramolecular 1,3-dipolar cycloaddition, leading to chromene[4,3-b]pyrrolidines. Two reaction conditions are used: (a) microwave-assisted heating (200 W, 185 °C) of a neat mixture of reagents, and (b) conventional heating (170 °C) in PEG-400 as solvent. In both cases, a mixture of two epimers at the α-position of the nitrogen atom in the pyrrolidine nucleus was formed through the less energetic endo-approach (B/C ring fusion). In many cases, the formation of the stereoisomer bearing a trans-arrangement into the B/C ring fusion was observed in high proportions. Comprehensive computational and kinetic simulation studies are detailed. An analysis of the stability of transient 1,3-dipoles, followed by an assessment of the intramolecular pathways and kinetics are also reported. The two-component synthesis of chromene[4,3-b]pyrrolidines has been achieved under two different conditions. The strategy was used to obtain N-sulfonylated adducts with interesting biological activity. Calculations show that formation of W and S′ 1,3-dipoles determines the stereochemical outcome of the reaction, which involves asynchronous transition structures.

Pericyclic reactions of azafulvenium methides bearing internal dipolarophiles - synthesis of chromene and chromane derivatives

The reactivity of azafulvenium methides with internal dipolarophiles was explored as an approach to new chromene derivatives. 4,5-Dimethoxycarbonyl- and 5-ethoxycarbonyl- 4-phenylazafulvenium methides with a prop-2-ynyloxyphenyl substituent are converted into 2-[2-(2H-chromen- 8-yl)vinyl]-1H-pyrroles through a sequence of rearrangements. 4,5-Dimethoxycarbonylazafulvenium methide with a more-activated dipolarophile as well as the more-activated 5- (trifluoromethyl)azafulvenium methide with an unactivated alkyne could be trapped by [8π+2π] cycloadditions to afford 8,12a-dihydro-6H-chromeno[4,3-e]indolizines. 5-(Trifluoromethyl) azafulvenium methide with a 2-(3-methoxycarbonylprop- 2-enyloxy)phenyl substituent at C-1 participated in both intramolecular [8π+2π] and [4π+2π] cycloadditions to afford heterocycle-fused chromanes. The microwave-induced rearrangements of 3-[2-(prop-2-ynyloxy)phenyl]-1H,3Hpyrrolo[ 1,2-c]thiazoles afforded chiral 3-(2H-chromen-8-yl)- 1H,3H-pyrrolo[1,2-c]thiazoles.

Exploring O-stannyl ketyl and acyl radical cyclizations for the synthesis of γ-lactone-fused benzopyrans and benzofurans

The synthesis of a series of γ-lactone-fused benzopyrans and benzofurans, analogues of the pyranonaphthoquinone antibiotics, is reported. Preparation of the heterocycles was achieved by either O-stannyl ketyl or acyl radical cyclization of benzaldehyde pr

PPh3-mediated intramolecular conjugation of alkyl halides with electron-deficient olefins: Facile synthesis of chromans and relevant analogues

With the mediation of phosphine, the direct intramolecular coupling of two electrophiles-alkyl halides with electron-deficient olefins-has been successfully realized in an intramolecular conjugate addition manner. The reaction provides a new approach for

Organocatalytic asymmetric intramolecular [3+2] cycloaddition: A straightforward approach to access multiply substituted hexahydrochromeno[4,3-b] pyrrolidine derivatives in high optical purity

A chiral phosphoric acid-catalyzed intramolecular 1,3-dipolar cycloaddition of 4-(2-formylphenoxy)butenoates with amino esters provides hexahydromeno[4,3-b]pyrrolidine derivatives in high enantioselectivity (up to 94% ee).