55539-49-6

Upstream product

• 496-16-2 2.3-dihydrobenzofuran 
• 100-52-7 benzaldehyde 
• 6272-40-8 2-benzoylbenzofuran 
• 64-17-5 ethanol 
• 90-02-8 salicylaldehyde 
• 98-86-2 acetophenone 
• 4393-06-0 1-Phenyl-2-propen-1-ol 
• 56052-53-0 3-(2-hydroxy-phenyl)-1-phenyl-propan-1-one 
• 533-58-4 2-Iodophenol 
• 644-78-0 2-hydroxychalcone 
• 7732-18-5 water 
• 644-78-0 2-hydroxychalcone 

Downstream Products

• 494-12-2 flavan 

Relevant academic research and scientific papers

One-Pot Synthesis of O-Heterocycles or Aryl Ketones Using an InCl3/Et3SiH System by Switching the Solvent

An efficient one-pot synthesis of O-heterocycles or aryl ketones has been achieved using Et3SiH in the presence of InCl3 via a sequential ionic hydrogenation reaction by switching the solvent. This methodology can be used to construct C-O bonds and to prepare conjugate reduction products, including chromans, tetrahydrofurans, tetrahydropyrans, dihydroisobenzofurans, dihydrochalcones, and 1,4-diones in a facile manner. In addition, a novel plausible mechanism involving a conjugate reduction and a tandem reductive cyclization was verified by experimental investigations.

A Modular Synthesis of 2-Alkyl- and 2-Arylchromans via a Three-Step Sequence

A convergent three-step method for the synthesis of 2-substituted chromans is described. These results have been accomplished via the Heck coupling of readily accessible allylic alcohols and 2-iodophenols, followed by reduction and Mitsunobu cyclization. The utility and generality of this method is demonstrated through the synthesis of a series of 2-aryl-, 2-heteroaryl- and 2-alkylchromans, as well as an azachroman derivative. The asymmetric version of this approach via a Noyori-catalyzed ketone reduction and subsequent cyclization is likewise highlighted.

An efficient synthesis of flavans from salicylaldehyde and acetophenone derivatives

An efficient total synthesis of flavans from the reactions of salicylaldehyde and acetophenone derivatives is reported. The synthesis involves preparation of chalcones through an aldol reaction followed by reduction of both the double bond and the ketone using NaBH4 and an acetic acid mediated cyclization. Methoxy groups on the aromatic rings did not affect significantly the yields of the procedure.

Reductive lithiation of cyclic benzofused ethers: A source of oxygen-functionalised organolithium compounds

The reaction of 2,3-dihydrobenzofuran (1) with lithium and a catalytic amount of 4,4′-di-tert-butylbiphenyl (DTBB, 5%) in THF at 0°C for 1.5h, followed by addition of an electrophile [E+=H2O, tBuCHO, PhCH2CHO, Ph(CH2)2CHO, PhCHO, furfural, Me2CO, Et2CO, cyclopentanone, cyclohexanone, cyclooctanone, (-)-menthone] in THF at -78°C gives, after hydrolysis, compounds 3. Some diols 3 are easily transformed into 2-substituted chromans 6 under acidic reaction conditions. The reductive lithiation of chroman (7) at 20°C for 3h leads exclusively to the intermediate 8, which is formed through a dearylation process, and isomerises to the apparently more stable benzylic intermediate 9. The reaction of these intermediates with different electrophiles {E+=tBuCHO, PhCHO, furfural, Me2CO, [CH3(CH2)4]2CO, cyclopentanone, cyclohexanone, (-)-menthone, Ph2CO}, at -78°C in THF leads, after hydrolysis, to a mixture of regioisomers 10 and 11. The reaction of 2,3-benzofuran (12) with an excess of lithium and a catalytic amount of DTBB (5%) in THF at 0°C for 45min leads to dianionic intermediate 13 through a dealkylation process, which after hydrolysis gives 2-vinylphenol 14. In the case of 4H-chromene (15), reductive opening is performed at 20°C for 45min, a mixture of dearylation and dealkylation intermediates 16 and 17, respectively, is obtained (2:1 ratio) giving, after hydrolysis, 3-phenylpropanal (18) and 2-allylphenol (19).

Organolithium reagents from alkyl phenyl ethers

The reaction of primary alkyl or vinyl phenyl ethers (1) as well as 2,3- dihydrobenzofuran (3) with an excess of lithium powder and a catalytic amount of DTBB (5 %) in THF at room temperature leads to the corresponding organolithium intermediates, which by treatment with different electrophiles [H2O, D2O, Me3SiCl, Bu(t)CHO, PhCHO, Me2CO, Et2CO, (CH2)4CO, (CH2)5CO, PhCOMe] and final hydrolysis affords the expected products 2 and 4.

Amino-substituted flavans useful as anti-viral agents

Novel compounds of formula (IID) STR1 wherein either both X and Y represent groups independently selected from amino and lower alkylamino, or one of X and Y represents a group selected from amino and lower alkylamino and the other of X and Y represents a hydrogen atom have been found to be active against rhinoviruses and other viruses. Processes for producing these compounds include reduction of flavanone derivatives or of flavenes. Alternatively, reductive cyclization of chalcones affords the compounds. These may also be prepared by condensation of o-(substituted methyl)phenols with styrene derivatives. Pharmaceutical formulations and methods for the administration of the compounds are described.