13524-66-8

Upstream product

• 23925-16-8 (E)-3-(2-hydroxyphenyl)-1-phenylpropene 
• 71-43-2 benzene 
• 73406-52-7 2-O-methoxymethylbenzyl bromide 
• 54008-77-4 2-bromo-1-benzofuran 
• 4265-14-9 2-benzylbenzofuran 
• 100-39-0 benzyl bromide 
• 108-86-1 bromobenzene 
• 1745-81-9 o-Allylphenol 
• 90-02-8 salicylaldehyde 
• 73406-54-9 (2-Methoxymethoxyphenyl)methyl-methansulfonat 
• 5533-04-0 2-(methoxymethoxy)benzaldehyde 
• 5533-05-1 (2-methoxymethoxyphenyl)methanol 
• 100976-02-1 2-phenyl-3-(2-hydroxyphenyl)-1-propanol 
• 152955-16-3 methyl 3-(2-O-methoxymethylphenyl)-2-phenylpropanoate 

Downstream Products

• 13524-55-5 trans-3-Phenyl-1-(2-hydroxy-phenyl)-propen-1 

Relevant academic research and scientific papers

Photochemistry of allylphenol derivatives. Role of the phenolic and styrenic excited states in the behavior of bichromophoric cinnamylphenol

Irradiation of trans-2-cinnamylphenol (2a) in hexane, under argon, led to the cis isomer 2b, 2-benzyl-2,3-dihyrobenzofuran (3), and 2-phenyl-3,4- dihydro-2H-benzopyran (4). The presence of oxygen produced a marked decrease of the 2b yield, with a parallel enhancement of the pathway leading to 3 and 4. In benzene, the cyclization process was enhanced, together with the 3:4 ratio. The latter was less favored in the presence of photosensitizers with lower singlet energies, such as toluene, methyl benzoate, or p- dichlorobenzene. In the acetone-photosensitized reaction, a clean and efficient isomerization to 2b took place. These results, together with CNDO/S calculations, suggested involvement of the phenolic or the styrenic singlets in the cyclization to 3 or 4, respectively, and the styrenic triplet (partially quenched by oxygen) in the double bond isomerization to 2b. Addition of methanol to the benzene solutions of 2a partially quenched the photocyclization. By contrast, the formation of 4 was markedly enhanced in the presence of trimethylamine or triethylamine, which were also efficient fluorescence quenchers. The above observations evidenced a new route to product 4 involving electron transfer from the tertiary amine to excited trans-2-cinnamylphenol (2a). The key step in the photocyclization must be intramolecular excited-state proton transfer (ESPT) and appears to involve π-complexes of the type I, IIa, and IIb. Accordingly, direct irradiation of the o-acetyl derivative 9a resulted exclusively in isomerization to 9b, owing to chelation of the hydroxy group, which should prevent formation of the π- complexes and facilitate deactivation of the phenolic singlet, via intramolecular proton exchange.

Ruthenium NHC catalyzed highly asymmetric hydrogenation of benzofurans

H2-O-T! Aromatic O-heterocycles are a challenging substrates for asymmetric hydrogenation (H2). An in situ formed chiral N-heterocyclic carbene (NHC) ruthenium complex allows the high yielding, completely regioselective, and highly asymmetric hydrogenation of substituted benzofurans at room Temperature, giving valuable 2,3-dihydrobenzofurans (see scheme). Copyright

Synthesis of chromans via Pd-catalyzed alkene carboetherification reactions

A new method for the construction of 2-substituted and 2,2-disubstituted chromans via Pd-catalyzed carboetherification reactions between aryl/alkenyl halides and 2-(but-3-en-1-yl)phenols is described. These reactions effect formation of a C-O bond and a C-C bond to afford the chroman products in good yield, and also provide stereoselective access to tricyclic chroman derivatives.

Photoreactions of trans-1-o-Hydroxyphenyl-2-phenylcyclopropane

The photochemistry of trans-1-o-hydroxyphenyl-2-phenylcyclopropane, trans-1, was studied under a variety of experimental conditions. Direct irradiation through quartz in cyclohexane gave rise mainly to ring-expanded products, 2-phenyl-3,4-dihydro-2H-benzopyran, 2, 2-benzyl-2,3-dihydrobenzofuran, 3, and 1-o-hydroxyphenylindan, 4. The major products, 2 and 3, are rationalized by intramolecular proton transfer. However, a significant fraction of 3 is formed via ring-opening to cinnamylphenol, 5. An additional product, o-(α-cyclohexylmethyl)phenol, 7, suggests fragmentation of trans-1 and (formal) insertion of o-hydroxyphenylcarbene into cyclohexane. Direct irradiation in methanol produced methanol adducts 8 and 9 instead of 2, 3,4, or 7. Finally, acetone-sensitized irradiation of trans-1 resulted in geometric isomerization to cis-1; this result can be rationalized via a biradical intermediate.

The direct synthesis of isoflavans VIA α-alkylation of phenylacetates

Deprotonation of oxygenated phenylacetates and quenching of the enolates with oxygenated benzylic electrophiles, afforded 2,3-diarylpropanoates which served as precursors to the isoflavans following consecutive reduction and cyclization steps.

Ground and excited-state intramolecular interactions in phenol-olefin bichromophoric compounds

The intramolecular OH ... π interactions of the phenolic and olefinic chromophores in o-propenyl and o-butenyl phenols 1a-d in the ground and excited states have been studied by (a) ab initio Hartree-Fock calculations using the 3-21G and 6-31G** basis sets, (b) FTIR spectral measurements in the gas phase, (c) fluorescence emission studies and (d) product studies. Such interactions appear to play a key role in the photochemical behaviour of the four compounds.

THE FIRST DIRECT SYNTHESIS OF ISOFLAVANS VIA α-ALKYLATION OF PHENYLACETATES

Deprotonation of phenylacetates and quenching of the enolates with benzylic electrophiles, afford 2,3-diarylpropanoates which serve as precursors to isoflavans following consecutive reduction and cyclization steps.