6053-99-2

Upstream product

• 31702-30-4 cis-3-bromoflavan 
• 888-12-0 (E)-2'-hydroxy-chalcone 
• 6783-05-7 trans-2-phenylvinylboronic acid 
• 90-02-8 salicylaldehyde 
• 118-93-4 o-hydroxyacetophenone 
• 108-86-1 bromobenzene 
• 88187-08-0 2-acetoxy-3-bromoflavan-4-one 
• 494-13-3 2-phenyl-4H-chromene 
• 525-82-6 FLAVONE 
• 88187-02-4 3-bromo-2-methoxyflavan-4-one 
• 88186-90-7 2,3-cis-3-bromo-2-propionyloxyflavan 
• 88186-87-2 2,3-cis-2-acetoxy-3-bromoflavan 
• 487-25-2 2',4-dihydroxydihydrochalcone 
• 487-25-2 cis-4-hydroxyflavan 

Downstream Products

• 56052-53-0 3-(2-hydroxy-phenyl)-1-phenyl-propan-1-one 
• 1413850-65-3 C₁₅H₁₂⁽²⁾H₂O₂ 

Relevant academic research and scientific papers

Enantioselective Synthesis of Chromenes via a Palladium-Catalyzed Asymmetric Redox-Relay Heck Reaction

A palladium-catalyzed asymmetric redox-relay Heck reaction of 4H-chromenes and arylboronic acids has been successfully developed. The reaction proceeded in moderate to good yields with good to high enantioselectivities. The resulting product is an advanced intermediate of bio-active compound BW683C.

Protecting group-free use of alcohols as carbon electrophiles in atom efficient aluminium triflate-catalysed dehydrative nucleophilic displacement reactions

Benzylic and allylic alcohols are rendered electrophilic without chemical modification by the use of aluminium triflate as catalyst. The reaction succeeds with alcohol, thiol, carbon and nitrogen nucleophiles. When phenols are employed as nucleophiles, C-alkylation ensues. An advanced application of the method is demonstrated in the synthesis of 2H-chromenes and their N and S analogues.

Transition-Metal-Free Cross-Coupling of Indium Organometallics with Chromene and Isochroman Acetals Mediated by BF3·OEt2

A transition-metal-free coupling of triorganoindium reagents with benzopyranyl acetals mediated by a Lewis acid has been developed. The reaction of R3In with chromene and isochroman acetals in the presence of BF3·OEt2 afforded 2-substituted chromenes and 1-substituted isochromans, respectively, in good yields. The reactions proceed with a variety of triorganoindium reagents (aryl, heteroaryl, alkynyl, alkenyl, alkyl) using only 50 mol % of the organometallic, thus demonstrating the efficiency of these species. Preliminary mechanistic studies indicate the formation of an oxocarbenium ion intermediate in the presence of the Lewis acid.

Catalytic Enantioselective Synthesis of 2-Aryl Chromenes and Related Phosphoramidite Ligands and Catalyst Compounds

Methods to access 2-aryl chromene compounds via an asymmetric catalytic process.

Dioxomolybdenum Complexes as Excellent Catalysts for the Deoxygenation of Aryl Ketones to Aryl Alkenes

This work describes a new methodology for the selective deoxygenation of aryl ketones to the corresponding aryl alkenes catalyzed by dioxomolybdenum complexes using silanes as reducing agents. The best results were obtained with the system PhSiH3/MoO2Cl2(H2O)2 (5-10 mol %), which was very efficient for the deoxygenation of a large variety of aryl ketones to alkenes in excellent yields. This new methodology has the advantages of using an inexpensive, environmentally friendly, easily prepared, and air-stable catalyst in ether solution.

Intramolecular etherification and polyene cyclization of π-Activated Alcohols Promoted by Hot Water

Hot water, acting as a mildly acidic catalyst, efficiently promoted intramolecular direct nucleophilic substitution reactions of unsaturated alcohols with heteroatom or carbon nucleophiles. In a mixed solvent of water and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), polyene cyclizations using allylic alcohols as initiators gave the desired cyclized products, and in neat HFIP, a tricyclization reaction gave a tetracyclic product in 51% chemical yield.

Glycerol as an efficient medium for the Petasis borono-mannich reaction

The multicomponent Petasis borono-Mannich (PBM) reaction is a useful tool for the preparation of complex molecules in a single step from boronic acids, aldehydes/ketones, and amines. Here, we describe the use of glycerol in the PBM reaction of salicylalde

Metalloradical approach to 2H -chromenes

Cobalt(III)-carbene radicals, generated through metalloradical activation of salicyl N-tosylhydrazones by cobalt(II) complexes of porphyrins, readily undergo radical addition to terminal alkynes to produce salicyl-vinyl radical intermediates. Subsequent hydrogen atom transfer (HAT) from the hydroxy group of the salicyl moiety to the vinyl radical leads to the formation of 2H-chromenes. The Co(II)-catalyzed process can tolerate various substitution patterns and produces the corresponding 2H-chromene products in good isolated yields. EPR spectroscopy and radical-trapping experiments with TEMPO are in agreement with the proposed radical mechanism. DFT calculations reveal the formation of the salicyl-vinyl radical intermediate by a metalloradical-mediated process. Unexpectedly, subsequent HAT from the hydroxy moiety to the vinyl radical leads to formation of an o-quinone methide intermediate, which dissociates spontaneously from the cobalt center and easily undergoes an endocyclic, sigmatropic ring-closing reaction to form the final 2H-chromene product.

Lewis and Bronsted acid cocatalyzed reductive deoxyallenylation of propargylic alcohols with 2-nitrobenzenesulfonylhydrazide

Reductive deoxyallenylation of sterically hindered tertiary propargylic alcohols was realized on reaction with 2-nitrobenzenesulfonylhydrazide (NBSH) by the combined use of Lewis and Bronsted acid catalysts. This method features a broad substrate scope, m

Structurally diverse α-substituted benzopyran synthesis through a practical metal-free C(sp3)-H functionalization

A trityl ion-mediated practical C-H functionalization of a variety of benzopyrans with a wide range of nucleophiles (organoboranes and C-H molecules) at ambient temperature has been disclosed. The metal-free reaction has an excellent functional group tole