109797-45-7

Upstream product

• 109797-42-4 4-(2-cyclohexenyloxy)-1-benzopyran-2(H)-one 
• 5186-54-9 3-diazobenzopyran-2,4(3H)-dione 
• 110-83-8 cyclohexene 
• 1076-38-6 4-hydroxy[1]benzopyran-2-one 
• 1521-51-3 rac-3-bromocyclohexene 
• 1165952-91-9 cyclohexa-1,3-diene 
• 822-67-3 Cyclohex-2-enol 

Downstream Products

• 144709-85-3 3-(2'-cyclohexenyl)-4-acetoxy coumarin 

Relevant academic research and scientific papers

Acid-Catalyzed Regiodivergent Annulation of 4-Hydroxycoumarins with Isoprene: Entry to Pyranocoumarins and Pyranochromones

An acid-catalyzed regiodivergent formal [3+3] annulation of 4-hydroxycoumarins with isoprene is developed. A variety of pyranocoumarins were obtained exclusively in the presence of strong Br?nsted acid, while varying to Lewis acid delivered pyranochromones as main products. The protocol also features high atom-economy, wide substrate scope, easy scale-up, and good applications in natural product synthesis.

Rhodium(II)-Catalyzed Reactions of 3-Diazo-2,4-chromenediones. First One-Step Synthesis of Pterophyllin 2

Rhodium(II)-catalyzed reactions of 3-diazo-2,4-chromenediones 1-3 with a variety of substrates are described. Reactions of 1 with nitriles, isocyanates, and ketones give the corresponding 5-membered heterocycles in moderate yields, whereas those of 1 with

Ionic Liquids with Multi-Active Sites Synergistically Catalyzed Metal-Free Transformation of Alcohols Using Dimethyl Carbonate as an Environmental Solvent

One of the ultimate goals in organic synthesis is to develop metal-free, efficient and easily separable catalytic system for atom economic organic reactions in an environmental solvent. Direct substitution reaction of alcohols and hydrocarbon compounds is a significant and atom economic method for C?C bond formation. Herein, a metal-free and efficient catalytic system including recyclable pyridine-based ionic liquids with multiple active sites as the catalyst and dimethyl carbonate as the environmentally friendly solvent was developed for atom economic C3 substitution of 4-hydroxycoumarins with alcohols. Primary aromatic alcohols, secondary aliphatic and aromatic alcohols were suitable for the reaction, providing up to 99 % yield. The catalytic system could be easily scaled up to gram-scale with nearly quantitative yield. Coumatetralyl as commercial rodenticide could be prepared directly from commercially available 4-hydroxycoumarin and 1,2,3,4-tetrahydronaphthalen-1-ol. Racemic product derived from the reaction of (R)-1-phenylethanol and 4-hydroxycoumarin indicated the reaction was achieved through an SN1 pathway. The comparison of the activities and acidities of the ionic liquids demonstrated that there was no directly relationship between them. Control experiments showed that the reaction probably proceeded via carbocation, ether intermediate and synergistically promoted effect of hydrogen bonding between the ionic liquid with multi-active sites and substrates.

Direct catalytic benzylation of hydroxycoumarin - Efficient synthesis of warfarin derivatives and analogues

Effective metal-catalyzed benzylations of 4-hydroxycoumarin have been developed. Employing a low amount of a cheap, nontoxic, and air-stable catalyst the 3-alkylated hydroxycoumarins were isolated in high yields after short reaction times. Applying this new methodology two widely used anticoagulants phenprocoumon and coumatetralyl were synthesized applying mild reaction conditions. Georg Thieme Verlag Stuttgart New York.

N-Iodosuccinimide mediated regioselective heterocyclization of 3-cyclohex-2′-enyl-4-hydroxycoumarin

A number of 3-cyclohex-2′-enyl-4-hydroxy[1]benzopyran-2-ones are regioselectively cyclized by treatment with N-iodosuccinimide in acetonitrile to afford 9′-iodo-2′-oxabicyclo[3,3,1]nonano[4′,3′-c][1] benzopyran-2-ones in excellent yield.

Studies on cyclisation of 3--4-hydroxy-1-benzopyran-2(H)-one

Benzofurobenzopyran-6-one (9) has been synthesised from 3--4-hydroxy-1-benzopyran-2(H)-one (5) via oxymercuration with mercuric acetate in methanol followed by dehydrogenative demercuration with Pd-C in refluxing diphenyl ether.I

Further Investigation on -Sigmatropic Rearrangement of Allyl Ethers of 4-Hydroxycoumarin

Pyrolytic -sigmatropic rearrangements of 4-(2-methyl-allyloxy)coumarin (7), 4-(cyclohex-2-enyloxy)coumarin (8) and 4-cinnamyloxycoumarin (11) afford 4-hydroxy-3-(2-methylallyl)coumarin (9), 3-(cyclohex-2-enyl)-4-hydroxycoumarin (10) and trans-2,3-dih