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Using a focused microwave reactor, methylation with dimethyl carbonate (DMC) of 1,2- and 1,4-dihydroxybenzene derivatives, found in the product spectrum of lignin depolymerisation, leads to the respective aromatic bis-methyl ethers with excellent isolated yields. Stoichiometric as well as catalytic amounts of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) are effective for the bis-methylation of these dihydroxybenzenes at relatively mild temperatures (160–190 °C). Conversion of resorcinol (1,3-dihydroxybenzene) under similar conditions leads to a mixture of 1,3-dimethoxybenzene and methyl 2,4-dimethoxybenzoate. The unusual reactivity of resorcinol's phenyl ring towards DMC can be explained by the synergic effect of its two strongly activating ortho/para directing groups.

A practical and efficient method for the direct, regioselective conversion of vinylogous esters to haloresorcinols is reported. Control of the reaction conditions enables synthesis of either the 4- or 6-haloresorcinol isomers from a common precursor with excellent regiocontrol and high yield. The generality and functional group tolerance of this novel protocol is demonstrated. The utility of this methodology to access polyhaloresorcinols is also reported. These methods create useful functionalized building blocks for further synthetic applications.

A Bi4O5Br2 photocatalyst had been synthesized successfully through a facile, one-step, and energy-saving hydrolysis route. The crystal structure, morphology, composition, optical property, and specific surface area of the as-synthesized material were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, UV-vis diffuse reflection spectra and N2 adsorption–desorption isotherms, respectively. Moreover, the photocatalytic activity of Bi4O5Br2 for resorcinol degradation under visible light irradiation was investigated systematically. The results revealed that the as-prepared Bi4O5Br2 photocatalyst exhibited strong visible light absorption (band gap energy 2.0 eV), and large specific surface area (62.25 m2 g−1), which resulted in the enhanced photocatalytic performance for resorcinol degradation. Compared with BiOBr and P25, the photocatalytic activity of Bi4O5Br2 was appropriately 31 and 12 times higher, respectively. The active oxygen species of h+, ˙OH, and ˙O2− dominated the resorcinol degradation process over the Bi4O5Br2 photocatalyst. In addition, the relatively high stability of Bi4O5Br2 will benefit its practical application for the treatment of other organic pollutants.

Sulfonic acid-functionalized MIL-101(Cr) was established to be an active heterogeneous catalyst for the one-pot synthesis of 2-amino-4H-chromenes via a three-component condensation reaction between resorcinol, malononitrile and a diverse range of aromatic aldehydes in aqueous medium. Here, sulfonation of the parent MIL-101(Cr) has been carried out through a post synthetic modification (PSM) technique. The resulting MIL-101(Cr)–SO3H has been characterized by employing powder X-ray diffraction, N2 sorption, FESEM, EDS, FT-IR and TGA studies. Furthermore, the catalyst can easily be recovered and recycled without much change in catalytic activity.

The presented mini-review summarizes the results of our study of the condensation of resorcinol and its derivatives with phosphorylated acetals, aldehydes, and vinylphosphonates with an aim to prep...

The title compounds are prepared by cyclocondensation of resorcinol, benzaldehydes, and cyanoacetates.

Pyrano[2,3-c]carbazoles which are biologically valuable and synthetically challenging frameworks are synthesized in high yields over five steps from commercially available resorcinol. Palladium-catalyzed arylation remains a key step in this novel strategy. The versatility of this protocol has been demonstrated by the synthesis of naturally occurring alkaloid clauraila C and 7-methoxyglycomaurin. The anti-proliferative activity of these designed compounds (5a, 5f, and 5l) has been evaluated in a cancer cell line (MOLT-4). The molecular docking study revealed that this pyrano[2,3-c]carbazole class of molecules selectively occupies the colchicine binding site of the tubulin-polymer.

An atom-efficient, catalyst-free, and environmentally friendly approach towards the synthesis of substituted 1,4-dihydroquinolines (5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j) through a one-pot multicomponent reaction involving resorcinol, aromatic aldehyde, acetoacetanilide, and ammonium acetate has been developed. The reactions were carried out under both conventional and microwave irradiation conditions. In general, improvement in rate and yield were observed when reactions were carried out under microwave irradiation compared with classical conditions. Most of the new compounds possessed moderate to significant antibacterial and antifungal activities.

The preparation of substituted 2-amino-4H-chromenes by a Na2CO3-catalyzed reaction of malononitrile, benzaldehydes, and phloroglucinol or resorcinol in aqueous medium and at room temperature is reported. The merits of this procedure include limited use of organic solvents, easy workup technique, and high purity of products. The 2-amino-4H-chromenes were prepared in yields of 54–96%.

Candida antarctica lipase B proved to be a highly active biocatalyst for the direct acylation of phenolic hydroxy groups of substituted hydroquinones and resorcinols, which have rarely been reported so far. More importantly, the acylation reactions took place generally in a markedly regioselective manner: the hydroxy group remote from the substituent was preferentially acylated. In the case of substituted hydroquinones, the selectivity increased with the increase in the bulk of the substituent. Interestingly, the 1- O -monoacylated derivatives were obtained as the sole products in the case of 4-substituted resorcinols.

Benzenediol lactones are a structurally variable family of fungal polyketide metabolites possessing a macrolide core structure fused into a resorcinol aromatic ring. These compounds are widespread in fungi mainly in the genera such as Aigialus , Cochliobolus , Curvularia , Fusarium , Humicola , Lasiodiplodia , Penicillium and Pochonia etc . Most of these fungal metabolites were reported to possess several interesting biological activities, such as cytotoxicities, nematicidal properties, inhibition of various kinases, receptor agonists, anti-inflammatory activities, heat shock response and immune system modulatory activities etc . This review summarizes the research on the isolation, structure elucidation, and biological activities of the benzenediol lactones, along with some available structure–activity relationships, biosynthetic studies, first syntheses, and syntheses that lead to the revision of structure or stereochemistry, published up to the year of 2014. More than 190 benzenediol lactones are described, and over 300 references cited.

2-Bromo-3-methoxycyclohex-2-en-1-ones are readily alkylated at C-6 with reactive halides, and then treatment with DBU (2 equiv) in PhMe at room temperature results in smooth loss of bromide and aromatization to resorcinol monomethyl ethers of defined substitution pattern.

Calix[4]resorcinarene-based cavitands with a bowl-shaped aromatic cavity are widely used as scaffolds for covalently bound and self-assembled capsules. There are two main categories of calix[4]resorcinarene-based cavitands that are tetrafunctionalized at the upper (wider) rim: one category includes derivatives that have functionalized bridges between pairs of hydroxy groups of the calix[4]resorcinarene, and the second category includes derivatives with functional groups at the 2-position on the resorcinol ring and the methylene bridge between pairs of hydroxy groups. This review describes capsular self-assemblies of the latter type of methylene-bridge cavitands, which are formed through hydrogen bonds, metal-coordination bonds, and dynamic covalent bonds.

Efficient one-pot construction of functionalized dibenzannulated bicyclic-O,O-ketals is accomplished by CeCl3·7H2O–NaI (5 mol% each) catalyzed coupling of 2-hydroxychalcones with resorcinol/phloroglucinol via regioselective Michael addition–bicyclization cascade. The enhanced nucleophilicity driven reaction of phloroglucinol with two chalcone partners delivered facile access to unprecedented novel bisbicyclic-O,O-ketals. Installation of hydrogen donor phenolic function in the conformationally constrained bicyclic-O,O-ketal core make the designed targets potential anticoagulant candidates.

Efficient and facile synthesis of 7H-benzopyrano[3,2-c]coumarins has been achieved by mild base promoted reaction of 4-chloro-3-formylcoumarin with diversely functionalized resorcinols. All the products were obtained as pure precipitates from the reaction mixture and the structure of the product was confirmed by X-ray analysis.

An efficient and facile one-pot synthesis is described for the preparation of novel 2-amino-5-hydroxy-4H-chromene derivatives with a spirooxindole nucleus using Ca(OH)2-mediated three-component reactions of substituted resorcinols with isatins and malononitrile. This simple method provided a variety of biologically interesting diverse 2-amino-5-hydroxy-4H-chromene derivatives in moderate yields under mild reaction conditions.

Treatment of cyclopentene-1,3-diones (V) with lithium (phenylsulfonyl)methanide (II) and with excess amounts of BuLi leads to the formation of benzene-1,3-diols (VI).

TfOH-catalyzed condensation of catechol (I) with trifluoroacetophenones (II) affords previously unreported phenolic polyphenylalkane derivatives (III), while similar reactions of resorcinol and hydroquinone furnish the corresponding novel hydroxy-substituted xanthene derivatives (V) and (VII), respectively.

A facile synthesis of chromene-2-thiones by the Pechmann condensation of phenols and β-oxodithioesters catalyzed by AlCl 3 under solvent-free condition has been reported. The best results were obtained in the case of substituted phenols such as resorcinol, substituted resorcinol, and pyrogallol. The optimum condition was observed with the use of 10 mol % of AlCl 3 at 130 °C under solvent-free conditions. This method offers a wide scope for the synthesis of coumarins in good yields during a short period of time.

The combination of methyl 3,7-dioxo-2-diazo-4-octenoate from the zinc triflate catalyzed Mukaiyama–Michael reaction of methyl 3-tert-butylsilyloxy-2-diazobutenoate and 4-methoxy-3-buten-2-one with Michael acceptors (methyl vinyl ketone, N-phenylmaleimide, β-nitrovinylarenes) in the presence of a catalytic amount of base provides convenient access to highly substituted resorcinol derivatives. This transformation is achieved in an efficient one-pot multi-component transformation by the sequential addition of the reagents.

A highly efficient one-pot three-component regioselective synthesis of 2-amino-3-cyano-4 H -chromene and tetrahydrobenzo[ b ]pyran derivatives has been developed by annulation of aldehydes, malononitrile, and resorcinol or dimedone under reflux conditions in 2,2,2-trifluoroethanol without the use of a catalyst or any other additive.

We have developed novel Rh-catalyzed [n+1]-type cycloadditions of 1,4-enyne esters, which involve an acyloxy migration as a key step. The efficient preparation of functionalized resorcinols, including biaryl derivatives, from readily available 1,4-enyne esters and CO was achieved by Rh-catalyzed [5+1] cycloaddition accompanied by 1,2-acyloxy migration. When enyne esters had an internal alkyne moiety, the reaction proceeded by a [4+1]-type cycloaddition involving 1,3-acyloxy migration, leading to cyclopentenones.

Title reaction proceeds smoothly under ultrasound irradiation and under solvent-free conditions to give the tetracyclic pyrano[2,3-b]pyridines (V) with excellent regioselectivity.

Condensation of aniline (I) with resorcinol (II), subsequent O-methylation of condensation product (III) and cyclization of (V) furnishes 2-methoxyphenothiazine (VI) in an overall yield of 74%.

The AlCl3-mediated cyclocondensation of 2,3-dichloropyrazine derivatives with 2-naphthol or resorcinol monoalkyl ethers offers a direct synthesis of various polycyclic bis-fused furan derivatives.

Efficient condensation of resorcinol and various aromatic aldehydes in the presence of RuCl3·nH2O as a homogeneous catalyst under reflux conditions was investigated. It was found that a very simple method afforded good to excellent yields of the desired products.

Dibrominated resorcinol dimers were synthesized by reaction of 4-bromoresorcinol with aldehydes under reflux in ethanol in the presence of HCl. Subsequent dehalogenation yielded the corresponding monobrominated compounds and a fully dehalogenated dimer. Of the dimers, 6,6′-((4-hydroxyphenyl)methylene)bis(4-bromobenzene-1,3-diol) (4) displayed potent antibacterial activity and inhibitory activity against isocitrate lyase Candida albicans.

A variety of novel 2-amino-5-hydroxy-4 H -chromene derivatives with various substituents on the 4 H -chromene ring were efficiently synthesized by one-pot reactions of substituted resorcinols and various 2-benzylidenemalononitriles in the presence of calcium hydroxide in methanol at room temperature. This simple method provided 2-amino-5-hydroxy-4 H -chromenes with high yields under mild reaction conditions.

The condensation of 2-ethoxyethenyl- phosphonic dichloride with resorcinol and its derivatives in dichloromethane in the presence of trifluoroacetic acid results in the formation of new bicyclic phosphonates with an endocyclic PC bond. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 22:1–4, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20646

employing a CeCl3-catalyzed Pechmann condensation of resorcinol (II) and β-keto ester (I) under solvent-free conditions as key step

A mechanism involving Rh-catalyzed cyclocarbonylation of 3-acyloxy-1,4-enynes accompanied by 1,2-acyloxy-shift is proposed for the novel [5 + 1] type cycloaddition reaction.

Le cyclotetramere resorcinol-dodecanal forme une couche monomoleculaire stable a l'interface air/eau. Les interactions moleculaires de cette couche monomoleculaire avec des sucres sont etudiees par spectrometrie UV-visible, IR et XPS

A new water-soluble host molecule was synthesized by the diazo-coupling reaction of a resorcinol-based tetrameric cyclophane and p-sulfonatobenzenediazonium. In an aqueous system the product could include large guest molecules such as adamantane, pyrene, and coronene, the association constants being (2.0–4.6) ×104 M−1.

3,4,5,6-Tetrahydro-7-hydroxy-2-(1,3-dithian-2-yl)- 9-alkyl-2,6-methano-2H-1-benzoxocin derivatives are readily prepared by boron trifluoride etherate-catalyzed formation of 5-alkylresorcinols with 1-thioxolanyl-2-cyclohexenol. The yieldis the highest with 5-(1,1-dimethylheptyl)resorcinol. The one with 5-pentylresorcinol is higher than with 5-methylresordnol and resorcinol apparently because of steric effects. The yields of the product increase; 3a(7%), 3b(22%), 3c(38%) and 3d(50%).

Directed functionalisation of resorcinol and benzofuran rings was achieved by activation with a coordinated tricarbonylchromium(0) unit and vicinal or remote lithiation directed by methoxy or t-butyldiphenylsilyloxy groups respectively. The process was applied either before [to the geranylbenzofuran (16) for mulberrofuran B (5)] or after [for moracin C (2)] palladium catalysed coupling of the 2-stannylated benzofuran and the 5-iodinated resorcinol moieties. In addition moracin I (4) was synthesised by a Stille coupling of the stannylated benzofuran (6) with the phloroglucinol triflate (14). Application to the synthesis of albafuran A (3) gave, unexpectedly, the 3-geranylbenzofuran (11).

A wide variety of easily accesible 1,3-cyclohexanediones are readily transformed to substituted dimethyl resorcinols with iodine and methanol.

Under biomimetic conditions, both phloroglucinol and resorcinol cause significant inhibition of the oxidative conversion of dopa to dopachrome, a key step in the biosynthesis of melanin pigments. The major product (λmax = 377 nm) from oxidation of dopa in the presence of phloroglucinol was characterized as 2, containing the unusual tetrahydromethanobenzofuroazocine ring system. Another product, formed in somewhat smaller amount, was formulated as 3, arising from coupling of phloroglucinol with 2 dopaquinone derived units. Analogous cross coupling adducts 4 and 5 were obtained by reaction of dopa or dopa methylester with resorcinol, respectively. These results suggest the trapping of labile dopaquinone, generated in situ from oxidation of dopa, by the reactive phenolic compounds, leading to the novel adducts 2, 4 and 5.

Halogenated dihydric phenols (hydroquinones and resorcinols) undergo halogen metal exchange with nBuLi/TMEDA/THF or ether (inverse addition) under sonication, thereby generating a C,O,O-trilithiated species which can be trapped with electrophiles.

The esterification reaction of resorcinol with benzoic acid, followed by the Fries rearrangement towards benzophenones in a one-pot liquid phase operation was examined with several catalysts. Zeolite H-beta and ion-exchange resins (Amberlyst-15, Nafion-117) were found to be the best catalysts for both equilibrium reactions. More insight in the Fries rearrangement was obtained by carrying out the reaction with a series of substituted phenols and substituted benzoic acids, especially with zeolite H-beta as the catalyst. The esterification reaction of resorcinol with hindered benzoic acids (2-Me- and 2,6-diMe-benzoic acid) is relatively rapid and an intermediate acylium ion is suggested. Here the rate of the rearrangement to the benzophenones is catalyst dependent; with zeolite H-beta the rearrangement of resorcinol-2-Me-benzoate is fast (yield > 90%) and the rearrangement of resorcinol-2,6-diMe-benzoate is slow because of the pore dimensions of the zeolite (shape effect). With Amberlyst-15 as the catalyst both rearrangements are fast. n-Butylbenzene, p -Cl-toluene and n-decane are found to be good solvents in this one-pot reaction. The industrial chemical 2,4-dihydroxybenzophenone can be prepared in a 88% yield by a recycling procedure starting from benzoic acid and resorcinol with zeolite H-beta as the catalyst and with n-butylbenzene as the solvent. In contrast to the existing process the present approach is a clean method.