132295-00-2

Upstream product

• 1076-38-6 4-hydroxy[1]benzopyran-2-one 
• 943-88-4 4-(p-methoxyphenyl)-3-butene-2-one 
• 3815-30-3 4-(4-methoxyphenyl)-3-buten-2-one 

Relevant academic research and scientific papers

Green asymmetric synthesis of Warfarin and Coumachlor in pure water catalyzed by quinoline-derived 1,2-diamines

Simple enantiomerically pure C2-symmetric quinoline (isoquinoline)-derived 1,2-diamines were synthesized from the corresponding aldehydes via stereospecific diaza-Cope rearrangement with 2,2′-(1,2-diaminoethane-1,2-diyl)diphenol (HPEN). Efficient green synthesis of both enantiomers of the anticoagulant Warfarin and rodenticide Coumachlor was achieved in an aqueous medium via the asymmetric iminium-type Michael reaction in the presence of the catalysts 8e and (ent)-8e in combination with (R)- or (S)-mandelic acid, respectively. This procedure provides high enantioselectivity (up to 91% ee), which has never been attained for these bioactive compounds with the known catalysts under aqueous conditions. Nearly optically pure Warfarin (～99% ee) was prepared via a green isolation procedure, which included acidic precipitation of the crude product from a basic aqueous solution followed by single recrystallization. Furthermore, unlike the known primary amine-derived organocatalysts, the developed aqueous catalytic system does not produce parasitic byproducts and can be recovered and reused in the asymmetric reaction.

Organocatalytic Asymmetric Michael Reaction of Cyclic 1,3-Dicarbonyl Compounds and α,β-Unsaturated Ketones - A Highly Atom-Economic Catalytic One-Step Formation of Optically Active Warfarin Anticoagulant

A broad range of Michael adducts 3 were obtained by the organocatalytic asymmetric Michael addition of cyclic 1,3-dicarbonyl compounds 1 to α,β-unsaturated ketones 2. The reaction allows a one-step synthesis of the optically active anti-coagulant warfarin and several analogues 3 on a kilogram scale in up to 99% yield with 88% ee (>99.9% ee after a single recrystallization).

Asymmetric synthesis of warfarin and its analogs catalyzed by C 2-symmetric squaramide-based primary diamines

Novel C2-symmetric N,N′-bis(2-amino-1,2-diphenylethyl)squaramides with 1,2-di(pyridin-2-yl)ethane and 1,2-diphenylethane spacer groups were designed and applied as organocatalysts in asymmetric additions of 4-hydroxycoumarin and 4-hydroxy-6-methyl-2H-pyran-2-one to α,β-unsaturated ketones. Both enantiomers of the anticoagulant warfarin and its analogs were prepared in up to 96% yield and with 96% ee. Recyclability of the developed catalysts and synthetic utility of the prepared Michael adducts for asymmetric synthesis of potential chiral medications via acylation reactions were demonstrated.

A bis-Lewis basic 2-aminoDMAP/prolinamide organocatalyst for application to the enantioselective synthesis of Warfarin and derivatives

A new chiral sec-amine/amidine-base hybrid catalyst, 2-aminoDMAP/prolinamide, is reported, which is able to catalyze conjugate addition of 4-hydroxycoumarin and various benzylideneacetones, a reaction that directly gives anticoagulant Warfarin and its analogues, with good yields (70-87%) and enantioselectivities (58-72%).

Primary amine attached to an N-(carboxyalkyl)imidazolium cation: A recyclable organocatalyst for the asymmetric Michael reaction

A (1S,2S)-1,2-diphenylethane-1,2-diamine derivative modified with an N-(4-carboxybutyl)imidazolium cation and PF6- anion has been developed and applied as a recyclable organocatalyst of the asymmetric 1,4-conjugate addition of 4-hydroxy-2H-chromen-2-one to 1-substituted buten-3-ones or cyclohexen-3-one to afford corresponding Michael adducts in high yields (up to 97-%) and enantioselectivities (up to 90-% ee). The most active (S) enantiomer of the clinically useful anticoagulant warfarin was prepared in this way. The catalyst exhibited better recyclability than its known analog, which does not contain a carboxy group: it could be recycled 5 times in the reaction without a significant decrease in product yield or ee values. Gradual deactivation of the catalyst was caused by leaching during workup rather than by off-cycle reactions between the catalyst and reagents. The sustainability of ionic-liquid-supported primary-amine-derived recyclable chiral organocatalyst of practical important in asymmetric Michael reactions has been improved by incorporating a peripheral carboxylic group that suppresses undesirable off-cycle reactions during the catalytic process. Copyright

Asymmetric synthesis of warfarin and its analogues on water

The asymmetric Michael addition of 4-hydroxycoumarin to α,β-unsaturated ketones on water without organic co-solvents is reported to be catalysed by organic primary amines. The application of enantiomerically pure (S,S)-diphenylethylenediamine affords a series of important pharmaceutically active compounds in good to excellent yields (73-98%) and with good enantioselectivities (up to 76% ee) via reactions accelerated by ultrasound. In particular, our developments led to an efficient protocol for the 'solids on water' formation of the anticoagulant warfarin in both enantiomeric forms. The presented scalable and environmentally friendly organocatalytic approach affords the target drug in enantiomerically pure form.

Highly enantioselective synthesis of Warfarin and its analogs catalysed by primary amine-phosphinamide bifunctional catalysts

An efficient enantioselective Michael addition of 4-hydroxycoumarin to α,β-unsaturated ketones catalysed by primary amine-phosphinamide bifunctional catalysts has been developed. This reaction afforded Warfarin and its analogs in moderate to excellent yie

Chiral primary amine tagged to ionic group as reusable organocatalyst for asymmetric Michael reactions of C-nucleophiles with α,β-unsaturated ketones

The first primary amine-derived organocatalyst modified with an ionic group for asymmetric Michael reactions of C-nucleophiles with α,β- unsaturated ketones was synthesized. In the presence of this catalyst and an acidic co-catalyst (AcOH), hydroxycoumarin and its sulfur-containing analogue reacted with benzylideneacetone derivatives or cyclohexenone to afford the corresponding Michael adducts in high yields (up to 97%) and with reasonable enantioselectivity (up to 80%). The catalyst could be easily recovered and efficiently reused three times, afterwards, its activity and stereodifferentiating ability gradually declined. The analysis of recovered catalyst samples by ESI-MS allowed us to detect undesirable side reactions that poisoned the catalyst, and propose an approach for its reactivation. Copyright

Organocatalytic enantioselective michael addition of 4-hydroxycoumarin to α,β-unsaturated ketones: a simple synthesis of warfarin

A type of C2-symmetric secondary amine amide catalysts were developed for the asymmetric Michael addition of Ahydroxycoumarin to α,ss-unsaturated ketones. A series of important biologically and pharmaceutically active compounds were obtained in

Highly enantioselective Michael addition of cyclic 1,3-dicarbonyl compounds to α,β-unsaturated ketones

The highly enantioselective Michael addition of 1,3-cyclic dicarbonyl compounds to α,β-unsaturated ketones was reported to be catalyzed by an organic primary amine derived from quinine. A chiral anticoagulant drug, (S)-warfarin, was directly prepared in 96% ee, and other related important adducts were also obtained in excellent enantioselectivity (89-99% ee).