- On the deprotonation of η6-1,3-dimethoxybenzene-Cr(CO)3 derivatives: Influence of the reaction conditions on the regioselectivity
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The regioselectivity of deprotonation/alkylation reactions of η6-1,3-dimethoxybenzene-Cr(CO)3 (5), η6-1,3-dimethoxy-5-methylbenzene-Cr(CO)3 (6) and 2-substituted derivatives of these compounds was investigated.
- Schmalz, Hans-Guenther,Volk, Thorsten,Bernicke, Dirk,Huneck, Siegfried
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Read Online
- Preparation method of 3,5-dihydroxyamylbenzene
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The invention provides a preparation method of 3,5-dihydroxyamylbenzene. The preparation method comprises the following steps: with a 3,5-dialkoxy benzoate compound as a raw material, subjecting the 3,5-dialkoxy benzoate compound to reacting with valeronitrile to generate a beta-ketone nitrile compound, hydrolyzing a cyano group to generate a carboxylic acid compound, performing a decarboxylation reaction to obtain 3,5-dialkoxyphenylpentanone, performing Huang Ming-long reaction or catalytic hydrogenation to convert 3,5-dialkoxyphenylpentanone into 3,5-dialkoxyamylbenzene, and finally, reducing an alkoxy group into a phenolic hydroxyl group so as to obtain 3,5-dihydroxyamylbenzene. The preparation method provided by the invention overcomes the defects of high cost, complex route, low yield, poor purity and the like of traditional processes.
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Paragraph 0042; 0046; 0054-0055; 0058
(2021/06/12)
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- Design of Negative and Positive Allosteric Modulators of the Cannabinoid CB2Receptor Derived from the Natural Product Cannabidiol
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Cannabidiol (CBD), the second most abundant of the active compounds found in the Cannabis sativa plant, is of increasing interest because it is approved for human use and is neither euphorizing nor addictive. Here, we design and synthesize novel compounds taking into account that CBD is both a partial agonist, when it binds to the orthosteric site, and a negative allosteric modulator, when it binds to the allosteric site of the cannabinoid CB2 receptor. Molecular dynamic simulations and site-directed mutagenesis studies have identified the allosteric site near the receptor entrance. This knowledge has permitted to perform structure-guided design of negative and positive allosteric modulators of the CB2 receptor with potential therapeutic utility.
- Navarro, Gemma,Gonzalez, Angel,Sánchez-Morales, Adrià,Casajuana-Martin, Nil,Gómez-Ventura, Marc,Cordomí, Arnau,Busqué, Félix,Alibés, Ramon,Pardo, Leonardo,Franco, Rafael
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p. 9354 - 9364
(2021/07/19)
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- CANNABINOID DERIVATIVES
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This disclosure relates to cannabinoid derivatives of formula (I), pharmaceutical compositions comprising them, and methods of using the cannabinoid derivatives in treating or preventing a diseases associated with a cannabinoid receptor in a subject in ne
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Paragraph 0130; 0139; 0206
(2021/02/12)
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- CANNABIGEROL DERIVATIVES AND USE THEREOF AS CANNABINOID RECEPTOR MODULATORS
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The synthesis of a range of pentylbezene- 1,3-diol compounds of formula I is disclosed. These compounds bind to cannabinoid 1 and 2 receptors (CB1 and CB2), and are thus presumed to be useful in modulating the activity of such receptors. Accordingly, the
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Paragraph 0128
(2021/06/04)
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- Synthesis method of 3, 5-dihydroxypentene benzene
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The invention provides a synthesis method of 3, 5-dihydroxypentene benzene. The synthesis method comprises the following steps: reacting 3, 5-dimethoxyphenol used as a raw material with a sulfonate halide reagent to generate sulfonate, carrying out cross-coupling reaction with a nucleophilic reagent to introduce amyl, and finally reducing methoxyl into phenolic hydroxyl, thereby obtaining the product 3, 5-dihydroxypentene benzene. The synthesis method solves the defects of high cost, complex route, low yield, poor purity and the like of the traditional process.
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Paragraph 0039; 0042
(2020/07/21)
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- METHODS FOR SYNTHESIS OF CANNABINOID COMPOUNDS
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The present invention provides simple synthetic routes for the preparation of cannabinoid compounds such as CBD, CBDV, THC, THCV, CBN, HU-308, CBG, CBC, and derivatives thereof, which are stereoselective and provide the desired cannabinoid compound in high yield.
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Paragraph 0078-0080
(2020/03/02)
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- Synthesis, inhibitory activity and in silico docking of dual COX/5-LOX inhibitors with quinone and resorcinol core
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Based on the significant anti-inflammatory activity of natural quinone primin (5a), series of 1,4-benzoquinones, hydroquinones, and related resorcinols were designed, synthesized, characterized and tested for their ability to inhibit the activity of cyclooxygenase (COX-1 and COX-2) and 5-lipoxygenase (5-LOX) enzymes. Structural modifications resulted in the identification of two compounds 5b (2-methoxy-6-undecyl-1,4-benzoquinone) and 6b (2-methoxy-6-undecyl-1,4-hydroquinone) as potent dual COX/5-LOX inhibitors. The IC50 values evaluated in vitro using enzymatic assay were for compound 5b IC50 = 1.07, 0.57, and 0.34 μM and for compound 6b IC50 = 1.07, 0.55, and 0.28 μM for COX-1, COX-2, and 5-LOX enzyme, respectively. In addition, compound 6d was identified as the most potent 5-LOX inhibitor (IC50 = 0.14 μM; reference inhibitor zileuton IC50 = 0.66 μM) from the tested compounds while its inhibitory potential against COX enzymes (IC50 = 2.65 and 2.71 μM for COX-1 and COX-2, respectively) was comparable with the reference inhibitor ibuprofen (IC50 = 4.50 and 2.46 μM, respectively). The most important structural modification leading to increased inhibitory activity towards both COXs and 5-LOX was the elongation of alkyl chain in position 6 from 5 to 11 carbons. Moreover, the monoacetylation in ortho position of bromo-hydroquinone 13 led to the discovery of potent (IC50 = 0.17 μM) 5-LOX inhibitor 17 (2-bromo-6-methoxy-1,4-benzoquinone) while bromination stabilized the hydroquinone form. Docking analysis revealed the interaction of compounds with Tyr355 and Arg120 in the catalytic site of COX enzymes, while the hydrophobic parts of the molecules filled the hydrophobic substrate channel leading up to Tyr385. In the allosteric catalytic site of 5-LOX, compounds bound to Tyr142 and formed aromatic interactions with Arg138. Taken together, we identified optimal alkyl chain length for dual COX/5-LOX inhibition and investigated other structural modifications influencing COX and 5-LOX inhibitory activity.
- Sisa, Miroslav,Dvorakova, Marcela,Temml, Veronika,Jarosova, Veronika,Vanek, Tomas,Landa, Premysl
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- METHOD FOR THE METAL-FREE PREPARATION OF A BIARYL BY A PHOTOSPLICING REACTION AND THEIR USES
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The present invention relates to a method for the metal-free preparation of a biaryl compound by a photosplicing reaction and its use in the preparation of chemical compounds, preferably of active ingredients e.g. in the fields of pharmaceuticals and agrochemicals. In particular, it refers to a method for the regiocontrolled preparation of a biaryl compound of formula (I): Ar-Ar' by photochemically reacting a precursor compound of formula (II): Ar-L-Ar' to form a biaryl compound of general formula: Ar-L-Ar' (II) → Ar-Ar' (I) wherein Ar and Ar', independently of each other, represent an unsubstituted or substituted C6-C20 aryl group or a heteroaryl group with 5–20 ring atoms selected from carbon, nitrogen, oxygen and sulfur, and L represents a group –X–Y–Z– as defined herein. The biaryl compounds are generally suitable as intermediates or key building blocks in a very broad spectrum of organic chemical syntheses and their respective utilities. Their use within the field of synthesis of active ingredients is an aspect of the invention, and their use in the preparation of pharmaceutically active ingredients is particularly preferred.
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Page/Page column 39; 53; 54; 55
(2019/06/11)
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- SYNTHESIS OF CANNABINOIDS
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Provided are synthesis processes and intermediates for preparing cannabinoids and analogs.
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Paragraph 0140-0141
(2019/02/05)
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- Enantioselective Total Synthesis of Cannabinoids - A Route for Analogue Development
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A practical synthetic approach to Δ9-tetrahydrocannabinol (1) and cannabidiol (2) that provides scalable access to these natural products and should enable the generation of novel synthetic analogues is reported.
- Shultz, Zachary P.,Lawrence, Grant A.,Jacobson, Jeffrey M.,Cruz, Emmanuel J.,Leahy, James W.
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supporting information
p. 381 - 384
(2018/01/27)
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- Metal-Free Synthesis of Pharmaceutically Important Biaryls by Photosplicing
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Many pharmaceuticals feature biaryl motifs that are crucial for their binding to the target. Yet, benchmark methods for selective cross-couplings rely on highly toxic heavy metal catalysts, which are unfavorable in the synthesis of pharmaceuticals. Metal-free coupling reactions, on the other hand, may require harsh conditions and lack selectivity. We report a novel, metal-free cross-coupling reaction that involves the tethering of two phenyl groups by a temporary, traceless sulfonamide linker that directs a photochemical aryl fusion into a single coupling product. The perfect regio- and chemoselectivity of the reaction could be rationalized by a cyclic intermediate, which fragments into the biaryl and volatile side products. Using a flow reactor, we synthesized numerous substituted biaryl building blocks for important therapeutics in high yields, such as antibiotics, antitumor, neuroprotective and cholesterol-lowering agents as well as antiarthritic non-steroidal antiinflammatory drugs (NSAIDs). The new method was successfully employed in a total synthesis of cannabinol, an important analgesic and antiemetic therapeutic. We also report a metal-free synthesis of key building blocks used for the preparation of sartans, antihypertensive agents that rank among the top blockbuster drugs worldwide. This safe and convenient protocol is a valuable alternative for the widely used metal-dependent aryl cross-coupling methods.
- Kloss, Florian,Neuwirth, Toni,Haensch, Veit G.,Hertweck, Christian
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supporting information
p. 14476 - 14481
(2018/09/06)
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- Nickel-Catalyzed C-O Bond-Cleaving Alkylation of Esters: Direct Replacement of the Ester Moiety by Functionalized Alkyl Chains
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Two efficient protocols for the nickel-catalyzed aryl-alkyl cross-coupling reactions using esters as coupling components have been established. The methods enable the selective oxidative addition of nickel to acyl C-O and aryl C-O bonds and allow the aryl-alkyl cross-coupling via decarbonylative bond cleavage or through cleavage of a C-O bond with high efficiency and good functional group compatibility. The protocols allow the streamlined, unconventional utilization of widespread ester groups and their precursors, carboxylic acids and phenols, in synthetic organic chemistry.
- Liu, Xiangqian,Jia, Jiaqi,Rueping, Magnus
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p. 4491 - 4496
(2017/07/24)
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- Concise access to primin, miconidin and related natural resorcinols
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An efficient and short synthetic procedures affording the biologically active natural products primin, miconidin, olivetol, grevillol, and cardol (adipostatin A) in high yields are reported. The two strategies involve Sonogashira and Suzuki cross-couplings as the crucial steps for the installation of the alkyl side-chains. Syntheses start from cheap, commercially available 1-bromo-3,5-dimethoxybenezene to obtain 1,3-dimethoxy-5-(alk-1-yn-1-yl)benzene as the key intermediate. This intermediate can be easily and economically oxidized to provide primin in excellent overall yield while avoiding undesired side products by the virtue of its symmetry. The demethylation of the key intermediate affords natural resorcinols olivetol, grevillol, and cardol, respectively. The reduction of primin provides its hydroquinone derivative miconidin.
- Sisa, Miroslav,Dvorakova, Marcela,Vanek, Tomas
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p. 5297 - 5301
(2017/08/04)
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- Acceleration of CuI-catalyzed coupling reaction of alkyl halides with aryl Grignard reagents using lithium chloride
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In the presence of LiCl, CuI-catalyzed coupling reaction of R(alkyl)-X with Ar(aryl)MgBr at rt was completed within 2 h. Effective leaving groups X in R-X were Br, I, OTs, but not Cl. Grignard reagents ArMgBr with both standard and bulky Ar such as 2-MeC
- Nakata, Kenya,Feng, Chao,Tojo, Toshifumi,Kobayashi, Yuichi
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p. 5774 - 5777
(2014/12/11)
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- Synthesis of cannabinol by a modified Ullmann-ziegler cross-coupling
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Cannabinol, a pharmaceutically interesting component of cannabis, was prepared by a modified Ullmann-Ziegler cross-coupling. Using easily obtainable starting materials, this convergent approach allows facile access to a variety of cannabinol derivatives. Georg Thieme Verlag Stuttgart New York.
- Nüllen, Max P.,G?ttlich, Richard
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p. 1109 - 1112
(2013/06/27)
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- Solid-Phase Reactive Chromatography (SPRC): A new methodology for wittig and horner-emmons reactions on a column under microwave irradiation
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A new methodology named solid-phase reactive chromatography (SPRC), which combines reaction, separation, and purification into a single unit for the preparation of small samples, is described. This method was illustrated in the synthesis of some natural bioactive compounds, namely, methoxylated analogues of resveratrol, alkylresorcinols, and 5-aryl-2,4-pentadienoates, over a column of alumina-KF under microwave irradiation by using the Wittig and HornerEmmons reactions. This approach permitted the preparation of the target olefins with high purity and good to excellent yields in short reaction times.
- Dakdouki, Saada C.,Villemin, Didier,Bar, Nathalie
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experimental part
p. 333 - 337
(2010/04/02)
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- Synthesis of chiloglottones - Semiochemicals from sexually deceptive orchids and their pollinators
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A five-step synthesis of monoalkyl- and 2,5-dialkyl-1,3-cyclohexanediones (1) is described via a sequence involving sequential Birch reductions and alkylations from the readily accessible and inexpensive starting material, 3,5-dimethoxybenzoic acid. Two approaches were considered in which alkylation at C-2 occurs either prior or subsequent to the proposed reduction. The successful route, in which Birch reduction of a 3-alkyl resorcinol derivative (3) precedes alkylation was applied in the synthesis of chiloglottone 1 (1dc), in 58% overall yield. Chiloglottone 1 is a member of a new class of natural products, representing a known sex pheromone of the thynnine wasp Neozeleboria cryptoides and pollinator attractant in the Australian sexually deceptive orchid genus Chiloglottis. The synthetic homologues were assessed for their biological activity via electroantennographic detection.
- Poldy, Jacqueline,Peakall, Rod,Barrow, Russell Allan
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supporting information; experimental part
p. 4296 - 4300
(2009/12/06)
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- MONOACYLGLYCEROL LIPASE INHIBITORS FOR MODULATION OF CANNABINOID ACTIVITY
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Disclosed are compounds and compositions that inhibit the action of monoacylglycerol lipase (MGL) and fatty acid amide hydrolase (FAAH), methods of inhibiting MGL and FAAH, methods of modulating cannabinoid receptors, and methods of treating various disorders related to the modulation of cannabinoid receptors.
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Page/Page column 97
(2009/05/28)
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- D3h-symmetrical hydrogen-bonding unit as a saccharide recognition and self-assembling module
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(Chemical Equation Presented) A D3h-symmetrical triresorcinol module 1,3,5-tris(2,6-dihydroxy-4-pentylphenyl)benzene (3) was investigated in terms of its hydrogen-bonding ability for glycoside recognition and self-association. When 3 was treate
- Abe, Hajime,Horii, Asuka,Matsumoto, Shinya,Shiro, Motoo,Inouye, Masahiko
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supporting information; experimental part
p. 2685 - 2688
(2009/05/26)
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- Synthesis of (-)-Δ9-trans-tetrahydrocannabinol: Stereocontrol via mo-catalyzed asymmetric allylic alkylation reaction
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(Chemical Equation Presented) Δ9-THC is synthesized in enantiomericaly pure form, where all of the stereochemistry is derived from the molybdenum-catalyzed asymmetric alkylation reaction of the extremely sterically congested bis-ortho-substitut
- Trost, Barry M.,Dogra, Kalindi
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p. 861 - 863
(2007/10/03)
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- The Diels-Alder approach towards cannabinoids
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Starting from the efficient synthesis of benzopyrans by base-catalyzed condensation reactions between substituted 2-hydroxybenzaldehydes and α,β-unsaturated aldehydes, thermal, Lewis acid catalyzed and enantioselective organo-promoted Diels-Alder reactions towards the tricyclic cannabinoid system are presented. The procedures are exemplified by the synthesis of a pentacycle and various tricycles respectively, in up to 95% enantiomeric excess and provide a versatile entry to this group of natural products with tetrahydrocannabinol (THC) being the most prominent one. Most published strategies are based on the formation of the tricyclic system by condensation between readily available phenols and monoterpenes, whereas we present a novel approach to cannabinoid derivatives based on a modular synthesis. Georg Thieme Verlag Stuttgart.
- Lesch, Bernhard,Toraeng, Jakob,Nieger, Martin,Braese, Stefan
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p. 1888 - 1900
(2007/10/03)
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- Synthesis of side chain specifically deuterated (-)-Δ9-tetrahydrocannabinols
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(-)-Δ9-Tetrahydrocannabinols specifically deuterated at the n-pentyl side chain were prepared using the corresponding resorcinols as key intermediates. To obtain the deuterated resorcinols we developed conditions under which no deuterium scramb
- Nikas, Spyros P.,Thakur, Ganesh A.,Makriyannis, Alexandros
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p. 1065 - 1076
(2007/10/03)
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- Synthesis of both enantiomers of hiburipyranone
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Both enentiomers of hiburipyranone, a cytotoxic metabolite of marine sponge, was synthesized employing Sharpless' asymmetric dihydroxylation as a key step and absolute configuration of the natural compound at C-3 position was determined to be R.
- Uchida, Kanako,Watanabe, Hidenori,Kitahara, Takeshi
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p. 8975 - 8984
(2007/10/03)
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- Synthesis of ardisinol II
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The first and also a concise synthesis of ardisinol II by two routes in excellent yields are described.
- Sun, Wei Yan,Zong, Qin,Gu, Rue Lin,Pan, Bai Chuan
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p. 1619 - 1622
(2007/10/03)
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- Reductive lithiation of arylalkyl methyl ethers
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We have investigated the reductive cleavage of arylalkyl methyl ethers with an excess of lithium metal and a catalytic amount of naphthalene. The reaction proceeds regioselectively in the presence of various substituents on the aromatic ring, allowing access to a wide array of arylalkyl lithium derivatives some of which are not easily accessible by conventional methods.
- Azzena, Ugo,Carta, Simonetta,Melloni, Giovanni,Sechi, Alessandra
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p. 16205 - 16212
(2007/10/03)
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- A simple synthesis of the natural 2,5-dialkylresorcinol free radical scavenger antioxidant: Resorstatin
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3,5-Dimethoxybenzoic acid 3 has been transformed into olivetol dimethyl ether 6 in three steps in 79% yield. Directed ortho-metallation-alkylation of 6, followed by boron tribromide demethylation resulted in a simple and inexpensive synthesis of resorstatin, in 70% overall yield from 3.
- Combes, Sebastien,Finet, Jean-Pierre
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p. 3769 - 3778
(2007/10/03)
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- Simple synthesis of 5-substituted resorcinols: A revisited family of interesting bioactive molecules
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The reaction of 3,5-dimethoxybenzyl trimethylsilyl ether (3) with different aldehydes (n-PrCHO, n-C11H23CHO, MeCHO, PhCHO) in the presence of lithium powder and a catalytic amount of naphthalene (4 mol %) gave, after hydrolysis, the expected alcohols 4 in moderate yields. The dehydroxylation of these compounds through the corresponding mesylates 5 or directly from benzylic derivatives by catalytic hydrogenation, afforded compounds 6, which are finally demethylated to yield 5-alkyl-3,5-dihydroxyresorcinols, such as olivetol (7a), grevillol (7b), 1,3-dihydroxy-5-propylbenzene (7c), or dihydropinosilvine (7d). Dehydration of alcohol derivatives 4 followed by demethylation led to hydroxylated stilbene-type structures, such as pinosilvine (9d), resveratrol (9e), or piceatannol (9f), which in some cases can be hydrogenated to give saturated molecules such as combretastanin B-4 tetramethyl ether (6f) or chrysotobibenzyl (6g). Finally, when the naphthalene-catalyzed lithiation of compound 3 was performed in the presence of other electrophiles [Me3SiCl, t-BuCHO, CH3(CH2)4CHO, 4-Me3SiOC6H4CHO, (CH2)5CO, PhN = C = O, PhN = CHPh], the expected reaction products 12 were isolated, after hydrolysis.
- Alonso, Emma,Ramon, Diego J.,Yus, Miguel
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p. 417 - 421
(2007/10/03)
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- A New Synthesis of 1-n-Alkyl-3,5-dimethoxybenzenes (Olivetol Dimethyl Ether and Homologs)
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An efficient method is reported for the synthesis of 1-n-alkyl-3,5-dimethoxybenzenes, useful intermediates in the synthesis of cannabinoids, from the readily available and cheap 3,4,5-trimethoxybenzoic acid.The key step is the electron-transfer induced highly regioselective demethoxylation of 1-n-alkyl-3,4,5-trimethoxybenzenes.
- Azzena, Ugo,Denurra, Teresa,Fenude, Emma,Melloni, Giovanni,Rassu, Gloria
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- Thermal Decomposition of Lichen Depsides
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The thermal decomposition of the following lichen depsides has been described: lecanoric acid, gyrophoric acid, evernic acid, perlatolic acid, planaic acid, confluentic acid, atranorin, 4-O-demethylbarbatic acid, and sekikaic acid.Main reaction products are decarboxylated compounds, phenolic units, rearranged depsides, and xanthones.Triethylammonium salts of depside carboxylic acids decompose at reasonably lower temperature than the corresponding free acids. - Keywords: Lichen Depsides, Thermal Decomposition
- Huneck, Siegfried,Schmidt, Juergen,Tabacchi, Raffaele
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p. 1283 - 1289
(2007/10/02)
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- Regioselective 4-Demethoxylation of 1-n-Alkyl-3,4,5-trimethoxybenzenes: a Key Step in the Synthesis of Olivetol and its Homologues
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Selective removal of the 4-methoxy group in n-alkyl-3,4,5-trimethoxybenzenes was performed under electron-transfer conditions; a new synthesis of olivetol dimethyl ether is described.
- Azzena, Ugo,Denurra, Teresa,Melloni, Giovanni,Rassu, Gloria
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p. 1549 - 1550
(2007/10/02)
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- BIOLOGICALLY ACTIVE PHENOLIC METABOLITES OF A VERTICICLADIELLA SPECIES
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The metabolites produced when a Verticicladiella species (Canadian Forestry Service strain C728), the causative agent of the black stain root disease of many conifers, is grown in liquid culture have been investigated.Orcinol, orcinol monomethyl ether, 1,3,6,8-tetrahydroxyanthraquinone, and the α-L-rhamnopyranosides of orcinol and orcinol methyl ether have been isolated and indentified.Orcinol methyl ether and its rhamnoside both show antibacterial activity and orcinol methyl ether also inhibits the growth of pine germlings.The general antibacterial activity of 5-alkylresorcinols and their monomethyl ethers is reported.-Key Word Index-Verticicladiella sp.; Deuteromycontina; blue-stain fungus; phytotoxin; phenols; methylorcinol rhamnoside; phenol monomethyl ethers; antiseptics.
- Ayer, William A.,Browne, Lois M.,Lovell, Sarah H.
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p. 2267 - 2272
(2007/10/02)
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- Condidymic Acid, a New Dibenzofuran from the Lichen Cladonia squamosula
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The dibenzofuran condidymic acid (3-hydroxy-7-methoxy-1,9-dipentyldibenzofuran-2-carboxylic acid) has been prepared by unambiguous synthesis and shown to co-occur with barbatic, thamnolic and didymic acids in Cladonia squamosula.
- Chester, Douglas O.,Elix, John A.
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p. 1501 - 1506
(2007/10/02)
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- Long-chain Phenols. Part 16. A Novel Synthesis of Homologous Orsellinic Acids and their Methyl Ethers
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By the novel reaction of 3,5-dimethoxyfluorobenzene with n-alkyl-lithium compounds, followed by carbonation, homologous orsellinic acid dimethyl ethers (6-alkyl-2,4-dimethoxybenzoic acids) have been obtained.The reactions proceeded best with the homologues of methyl-lithium.These reactions are considered to occur by way of 3,5-dimethoxybenzyne. 2,4-Dimethoxyfluorobenzene did not form an aryne but gave 3-fluoro-2,6-dimethoxybenzoic acid instead.Decomposition with water of alkyl-lithium reaction mixtures from 3,5-dimethoxyfluorobenzene yielded 5-n-alkylresorcinol dimethyl ethers.Demethylaton of 6-alkyl-2,4-dimethoxybenzoic acids with boron trichloride proceeded partially and selectively to give the 6-alkyl-2-hydroxy-4-methoxybenzoic acids, and completely with aluminium chloride to give the homologous orsellinic acids.Boron tribromide was less effective, but readily gave the 5-alkyl resorcinols from the corresponding dimethyl ethers.
- Durrani, Aziz A.,Tyman, John H. P.
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p. 1658 - 1666
(2007/10/02)
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