Naphthalene System Research Articles

Naphthalene System as Origin of Unconventionally Shaped Ferroelectric Liquid Crystals

Naphthalene System as Origin of Unconventionally Shaped Ferroelectric Liquid Crystals

Pseudomonas aeruginosa 142 uses a three-component ortho-halobenzoate 1,2-dioxygenase for metabolism of 2,4-dichloro- and 2-chlorobenzoate

Cell extracts of Pseudomonas aeruginosa 142, which was previously isolated from a polychlorinated biphenyl-degrading consortium, were shown to degrade 2,4-dichlorobenzoate, 2-chlorobenzoate, and a variety of other substituted ortho-halobenzoates by a reaction that requires oxygen, NADH, Fe(II), and flavin adenine dinucleotide. By using extracts that were chromatographically depleted of chlorocatechol and catechol 1,2-dioxygenase activities, products of the initial reaction with 2,4- or 2,5-dichlorobenzoate and 2-chlorobenzoate were identified by mass spectrometry as 4-chlorocatechol and catechol. In contrast to the well-characterized benzoate dioxygenases or the recently described 2-halobenzoate 1,2-dioxygenase from P. cepacia 2CBS (S. Fetzner, R. Müller, and F. Lingens, J. Bacteriol. 174:279-290, 1992) that possess two protein components, the P. aeruginosa enzyme was resolved by ion-exchange chromatography into three components, each of which is required for activity. To verify the distinct nature of this enzyme, we purified, characterized, and identified one component as a ferredoxin (M(r), approximately 13,000) containing a single [2Fe-2S] Rieske-type cluster (electron paramagnetic resonance spectroscopic values of gx = 1.82, gy = 1.905, and gz = 2.02 in the reduced state) that is related in sequence to ferredoxins found in the naphthalene and biphenyl three-component dioxygenase systems. By analogy to these enzymes, we propose that the P. aeruginosa ferredoxin serves as an electron carrier between an NADH-dependent ferredoxin reductase and the terminal component of the ortho-halobenzoate 1,2-dioxygenase. The broad specificity and high regiospecificity of the enzyme make it a promising candidate for use in the degradation of mixtures of chlorobenzoates.

Abc]-Annelated [18]annulenes

Synthesis of [18] annulenes realize for the first time by fusing naphthalene or phenanthrene systems to the 18-membered ring. The decisive synthetic step in each case is performed by a 3-fold cyclic condensation of the corresponding methyl phenylimino arenes. The anilino group is a bulky leaving group, which leads to an extreme stereoselectivity (E:Z> 1000:1)

Claisen rearrangement of prenyl ethers of isomeric acetylnaphthols and bisprenyl ethers of 4,6- and 2,4-diacetylresorcinols

Claisen rearrangements of the 3-methylbut-2-enyl(prenyl) ethers 3 and 9 of 2-acetyl-1-hydroxyand 1-acetyl-2-hydroxynaphthalenes 1 and 2 and the bis(3-methylbut-2-enyl) ethers 12 and 18 of 2,4-and 4,6-diacetylresorcinols 11 and 17 have been studied under a variety of thermal and catalytic conditions. 2-Acetyl-4-(3- methylbut-2-enyl) naphthalene-1-ol 4 was the sole product on rearrangement of compound 3, in DMA or neat. Under catalytic conditions 3,4-dihydro-2,2-dimethyl-2H-naphtho[1,2-b]pyran 7 was obtained in poor yield. An isomeric pyran, 1,2-dihydro-3,3-dimethyl-3H-naphtho[2,1-b]pyran 10(25–43%) was obtained under both thermal and catalytic conditions from 9. The rearrangement of 12 under thermal conditions (DMA and neat) furnished 3-acetyl-2,4-dihydroxy5-(3-methylbut-2-enyl)acetophenone 13 and 3,8-diisopropylbenzo[1,2-b: 3,4-b′]difuran 14. PdII mediated rearrangement of 12 gave only the partially deprenylated ether, 3-acetyl-4-hydroxy-2-(3-methylbut-2-enyloxy)acetophenone 15(29%). While the isomeric ether 18 gave the monoprenyl ether, 5-acetyl-4-hydroxy-2-(3-methylbut-2-enyloxy)acetophenone 19 in quantitative yield (95%). The rearrangement products were characterised and their formation rationalised in terms of allowed sigmatropic shifts ([3,3] prenyl and [1,5] H) followed by loss of prenyl or acetyl groups. The reactions of prenyl ethers are both comparable to those of the corresponding allyl ethers and consistent with the greater fixed double-bond character of the naphthalene system compared to that of benzene. Prenyl derivatives of benzene and naphthalene containing ortho-hydroxyacetophenone units were formed which have potential in synthesis.

ChemInform Abstract: Thermal Claisen Rearrangement of Allyl Ethers of Isomeric Acetylnaphthols.

Thermal Claisen rearrangement of the allyl ethers (3) and (12) of the isomeric 2-acetyl-1-hydroxy- and 1-acetyl-2-hydroxy-naphthalenes (1) and (2) has been studied by heating each in refluxing N,N-dimethylaniline (DMA) and neat at 185 °C under an N2 atmosphere. 2-Acetyl-4-allyl-1-hydroxynaphthalene (4), the sole product isolated from (3), was isolated in 56 and 88% yield respectively under the two sets of conditions. The rearrangement of the allyl ether (12) gave 3-acetyl-1-allyl-2-hydroxynaphthalene (13)(18%) and 2-acetoxy-1-allylnaphthalene (14)(23%) in N,N-DMA while in the neat rearrangement it gave (14) as the major product (70%) along with 1-allyl-2-hydroxynaphthalene (17)(20%). The rearrangement of the allyl ether (7), obtained on further allylation of (4), furnished 2,4-diallyl-1-hydroxynaphthalene (8), (15%) and (4)(15%) in DMA while it gave 1-acetoxy-2,4-diallylnaphthalene (9) as the sole product (67%) in the neat rearrangment. The rearrangement of the allyl ether (15), obtained by further allylation of (13), in DMA gave 3-acetyl-1,1-diallylnaphthalen-2(1H)-one (16)(20%) along with (13)(6%). The various rearrangement products have been characterised by their spectroscopic data (UV, IR, 1H NMR, and EI-MS) and the reactions rationalised by the allowed sigmatropic shifts such as [3,3] allyl, [1,5] acetyl followed by loss of allyl or acetyl groups. The significant differences noticed in the reactions of the isomeric series of allyl ethers are consistent with the greater fixed double-bond character of the naphthalene system compared to that of benzene as well as the positional isomerism that exists in the allyl ethers. The above Claisen rearrangement studies result in the isolation of some interesting naphthylallyl derivatives with orhto-hydroxyacetophenone units which form useful synthetic intermediates for preparing several naphthyl-α- and γ-pyrone derivatives of pharmacological activity.

1-(1-Chlorovinyl)-2,7-dimethoxynaphthalene

C14H13ClO2, Mr = 248.71, monoclinic, P21/n, a = 11.291 (1), b = 7.343 (1), c = 15.223 (2) A, beta = 90.899 (8) degrees, V = 1262.0 (5) A3, Z = 4, Dx = 1.309 g cm-3, lambda(CU K alpha) = 1.54184 A, mu = 26.0 cm-1, F(000) = 520, T = 299 K, R = 0.041 for 2405 observations (of 2516 unique data). The average deviation from planarity is 0.019 (2) A with a maximum of 0.035 (1) A for the fused rings. The dihedral angle between the naphthalene system and the chlorovinyl group is 101.93 (4) degrees. The methoxy group ortho to the chlorovinyl adopts a conformation with the methyl group anti to the neighboring alpha carbon of the ring, with a C-C-O-C torsion angle of -175.6 (2) degrees. The other methoxy group has the methyl syn to the neighboring alpha carbon, with a C-C-O-C torsion angle of 1.9 (3) degrees.

Thermal Claisen rearrangement of allyl ethers of isomeric acetylnaphthols

Thermal Claisen rearrangement of the allyl ethers (3) and (12) of the isomeric 2-acetyl-1-hydroxy- and 1-acetyl-2-hydroxy-naphthalenes (1) and (2) has been studied by heating each in refluxing N,N-dimethylaniline (DMA) and neat at 185 °C under an N2 atmosphere. 2-Acetyl-4-allyl-1-hydroxynaphthalene (4), the sole product isolated from (3), was isolated in 56 and 88% yield respectively under the two sets of conditions. The rearrangement of the allyl ether (12) gave 3-acetyl-1-allyl-2-hydroxynaphthalene (13)(18%) and 2-acetoxy-1-allylnaphthalene (14)(23%) in N,N-DMA while in the neat rearrangement it gave (14) as the major product (70%) along with 1-allyl-2-hydroxynaphthalene (17)(20%). The rearrangement of the allyl ether (7), obtained on further allylation of (4), furnished 2,4-diallyl-1-hydroxynaphthalene (8), (15%) and (4)(15%) in DMA while it gave 1-acetoxy-2,4-diallylnaphthalene (9) as the sole product (67%) in the neat rearrangment. The rearrangement of the allyl ether (15), obtained by further allylation of (13), in DMA gave 3-acetyl-1,1-diallylnaphthalen-2(1H)-one (16)(20%) along with (13)(6%). The various rearrangement products have been characterised by their spectroscopic data (UV, IR, 1H NMR, and EI-MS) and the reactions rationalised by the allowed sigmatropic shifts such as [3,3] allyl, [1,5] acetyl followed by loss of allyl or acetyl groups. The significant differences noticed in the reactions of the isomeric series of allyl ethers are consistent with the greater fixed double-bond character of the naphthalene system compared to that of benzene as well as the positional isomerism that exists in the allyl ethers. The above Claisen rearrangement studies result in the isolation of some interesting naphthylallyl derivatives with orhto-hydroxyacetophenone units which form useful synthetic intermediates for preparing several naphthyl-α- and γ-pyrone derivatives of pharmacological activity.

ChemInform Abstract: Synthesis of the 1H,5H‐Naphtho(1,8‐ef)(1,3)dithiocin System.

The titled new pericyclized naphthalene system has been prepared in four steps from 1,8-naphthalenedicarboxylic anhydride in an overall yield of 35–78%. The key step in the synthesis employed a dithioacetal-cyclization reaction of 1,8-bis(mercaptomethyl)naphthalene with carbonyl compounds using boron trifluoride etherate as a catalyst.

ChemInform Abstract: 1‐Acetyl‐2,7‐dimethoxynaphthalene

C14H14O3, Mr = 230.3, monoclinic, P2(1)/c, a = 8.8107 (9), b = 18.372 (3), c = 7.7512 (11) A, beta = 98.49 (1) degrees, V = 1240.9 (5) A3, Z = 4, Dx = 1.232 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 0.80 cm-1, F(000) = 488, T = 293 K, R = 0.047 for 1909 observations (of 2848 unique data). The average deviation from planarity is 0.017 (2) A with a maximum of 0.0285 (15) A for the fused rings. The dihedral angle between the naphthalene system and the acetyl group is 117.91 (6) degrees. The methoxyl group ortho to the acetyl adopts a conformation with the methyl group anti to the neighboring alpha-carbon of the ring, with a C-C-O-C torsion angle of -178.7 (2) degrees. The other methoxyl group has the methyl syn to the neighboring alpha-carbon, with a C-C-O-C torsion angle of -1.3 (3) degrees.

Synthesis of the 1H,5H-Naphtho[1,8-ef][1,3]dithiocin System

Abstract The titled new pericyclized naphthalene system has been prepared in four steps from 1,8-naphthalenedicarboxylic anhydride in an overall yield of 35–78%. The key step in the synthesis employed a dithioacetal-cyclization reaction of 1,8-bis(mercaptomethyl)naphthalene with carbonyl compounds using boron trifluoride etherate as a catalyst.

1-Acetyl-2,7-dimethoxynaphthalene.

C14H14O3, Mr = 230.3, monoclinic, P2(1)/c, a = 8.8107 (9), b = 18.372 (3), c = 7.7512 (11) A, beta = 98.49 (1) degrees, V = 1240.9 (5) A3, Z = 4, Dx = 1.232 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 0.80 cm-1, F(000) = 488, T = 293 K, R = 0.047 for 1909 observations (of 2848 unique data). The average deviation from planarity is 0.017 (2) A with a maximum of 0.0285 (15) A for the fused rings. The dihedral angle between the naphthalene system and the acetyl group is 117.91 (6) degrees. The methoxyl group ortho to the acetyl adopts a conformation with the methyl group anti to the neighboring alpha-carbon of the ring, with a C-C-O-C torsion angle of -178.7 (2) degrees. The other methoxyl group has the methyl syn to the neighboring alpha-carbon, with a C-C-O-C torsion angle of -1.3 (3) degrees.

Stopped-Flow Kinetics of the Formation and Decomposition of 2,4- and 4,4-Disubstituted Meisenheimer Complexes in the Reaction of 4-Piperidino-1,3-dinitrophenanthrene with Potassium Methoxide in Dimethyl Sulfoxide–Methanol

Abstract The formation of 2,4-disubstituted anionic σ complex, followed by the formation of 4,4-disubstituted one was confirmed by means of absorption and NMR spectra in the reaction of 4-piperidino-1,3-dinitrophenanthrene with potassium methoxide in DMSO–CH3OH. The rates and activation parameters were determined by kinetic studies using stopped-flow and conventional spectrophotometers. It was found, compared with the previous results on the naphthalene system that the presence of H5 of the title compound affects the rates differently.

The insertion and extrusion of heterosulfur bridges. XV. S‐bridging of 2,2′‐binaphthyl and 1‐(2‐naphthyl)cyclohexene. Studies on hydrodehalogenation during the reaction

AbstractRegioselectivity occurs in the sulfur‐bridging reactions of 2,2′‐binaphthyl (1) and 1‐(2‐naphthyl)cyclohexene (7) by means of hydrogen sulfide and a chromia‐alumina‐magnesia catalyst (designated I) in a flow apparatus at 550°. Thus, 1 gives a higher yield (6.1%) of dinaphtho[1,2–6:2′,l'‐d]thiophene from 1,1′‐bridging than of dinaphtho[1,2‐b:2′,3′‐d]thiophene (3.4%) from l,3′‐bridging. No product expected from 3,3′‐bridging was identified. Substrate 7 undergoes both dehydrogenation and bridging to yield 2‐phenylnaphthalene (8%), benzo[b]naphtho[2,1‐d]thiophene (9%) from alpha bridging, and benzo[b]naphtho[2,3‐d]thiophene (3%) from beta bridging into the naphthalene ring.Exploratory studies showed that either sulfided catalyst I or a sulfided molybdenum(VI) oxide‐alumina‐cobalt(II) oxide catalyst (II) effects hydrodehalogenation of various monohalo‐ and polyhaloarenes (where halo, X, is chloro or bromo) at 450–550°. In the biphenyl, phenanthrene, naphthalene, and pyrene systems, halogen was lost either under sulfur‐bridging conditions or under hydrogenolysis conditions, i.e. with methanol as a reactant. For every substrate the parent arene was isolated or identified as a reaction product. In selected experiments, acid HX was also identified in the effluent. Use of hydrogen sulfide as a reactant led to formation of dibenzothiophene and phenanthro[4,5‐bcd]thiophene as main products in the biphenyl and phenanthrene systems, respectively; while use of methanol as a reactant gave small amounts of methyl bromide (for X = Br) and methylarenes.

ChemInform Abstract: Mechanisms for Reactions of Halogenated Compounds. Part 5. Orientating Effects of Fluorine Substituents on Nucleophilic Substitution in Naphthalene and Other Polycyclic Systems

ChemInformVolume 19, Issue 19 Preparative Organic Chemistry ChemInform Abstract: Mechanisms for Reactions of Halogenated Compounds. Part 5. Orientating Effects of Fluorine Substituents on Nucleophilic Substitution in Naphthalene and Other Polycyclic Systems R. D. CHAMBERS, R. D. CHAMBERS Dep. Chem., Univ. Durham, Durham DH1 3LE, UKSearch for more papers by this authorM. J. SEABURY, M. J. SEABURY Dep. Chem., Univ. Durham, Durham DH1 3LE, UKSearch for more papers by this authorD. L. H. WILLIAMS, D. L. H. WILLIAMS Dep. Chem., Univ. Durham, Durham DH1 3LE, UKSearch for more papers by this authorN. HUGHES, N. HUGHES Dep. Chem., Univ. Durham, Durham DH1 3LE, UKSearch for more papers by this author R. D. CHAMBERS, R. D. CHAMBERS Dep. Chem., Univ. Durham, Durham DH1 3LE, UKSearch for more papers by this authorM. J. SEABURY, M. J. SEABURY Dep. Chem., Univ. Durham, Durham DH1 3LE, UKSearch for more papers by this authorD. L. H. WILLIAMS, D. L. H. WILLIAMS Dep. Chem., Univ. Durham, Durham DH1 3LE, UKSearch for more papers by this authorN. HUGHES, N. HUGHES Dep. Chem., Univ. Durham, Durham DH1 3LE, UKSearch for more papers by this author First published: May 10, 1988 https://doi.org/10.1002/chin.198819081Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume19, Issue19May 10, 1988 RelatedInformation

Mechanisms for reactions of halogenated compounds. Part 5. Orientating effects of fluorine substituents on nucleophilic substitution in naphthalene and other polycyclic systems

Separate activating effects have been determined for fluorine atoms as substituents at ortho-positions and at sites in the remote ring, relative to the position of attack by methoxide in methanol, in polyfluoronaphthalenes. Fluorine activates at sites in the remote ring that are adjacent to the centres of high charge density in the transition state, but is slightly deactivating when attached directly to these sites. Fluorine at ortho-positions activates. These results enable a simple model, which accounts for orientation of nucleophilic aromatic substitution, to be extended to perfluoropolycyclic compounds.

Cyclophan-Metall-Komplexe: Synthese und Kristallstruktur von ([2](l,4)Naphthalino[2]paracyclophan)gallium(I)-tetrabromogallat(III)/Cyclophane Metal Complexes: Synthesis and Crystal Structure of ([2]( 1,4)Naphthalino[2]paracyclophane)gallium(I) Tetrabromogallate(III)

Abstract The title complex has been prepared from Ga[GaBr4] and [2](1,4)naphthalino[2]paracyclophane in toluene as a solvent, and the crystal structure of this adduct determined by single crystal X-ray diffraction. The structure is composed of dimeric units Ga2[GaBr4]2 , which are crosslinked into sheets through Ga(I)-arene coordination. Both the benzene ring and the substituted ring of the naphthalene system are η6-bonded from the outer side of the cyclophane cage, each to an univalent metal. The benzene and the naphthalene form an interplane angle of 49.3°. The distance to the benzene ring (2.67 Å) is much shorter than the distance to the naphthalene (2.85 Å), suggesting a stronger complexation with the unperturbed π-system of the former. [2.2](l,4)Naphthalinophane forms no adduct with Ga[GaBr4], and with [2](l,5)naphthalino[2]paracyclophane secondary reactions are observed.

Energy-donor phosphorescence and energy transfer by exchange interaction in a rigid matrix

The decay of the energy-donor phosphorescence has been observed using a N2 laser on the benzophenone–naphthalene and p-methoxybenzaldehyde–naphthalene systems, and the results have been examined in the light of the theory developed by Inokuti and Hirayama for energy transfer by exchange interaction. Substantial discrepancies have been found between the theory and the observed phosphorescence decay curves, in particular, for the short time region after excitation. We have introduced the concept of the nonvanishing closest donor–acceptor intermolecular distance into the framework of the theory. Over the whole range of time, the experimental data have been found to agree with the theory thus amended.

Effect of catalyst size on coal liquefaction reactions and kinetics

Diffusion of reacting coal species through catalyst pores is an important factor in the kinetics of coal liquefaction reactions. The effect of diffusion was studied using a model naphthalene system and using Illinois #6 coal and asphaltenes and preasphaltenes derived from Illinois #6 solvent refined coal. These reactions were performed with four different presulfided NiMo/Al 2O 3 extrudate sizes (1/10″, 1/16″, 1/32″, and 1/64″) and with each catalyst in powdered (−200 mesh) form. Thermal reactions were also performed. The naphthalene reaction showed definite diffusional limitations at a reaction temperature of 300°C. The selectivity of naphthalene to intermediate product followed the theoretical prediction with decreasing particle size for a first order series reaction. Diffusional limitations were also observed in the coal liquefaction reactions. The upgrading of coal and preasphaltenes with large catalyst pellets produced much more conversion to products soluble in pentane, benzene, and methylene chloride/methanol than did the thermal reactions for each of the materials; however, little improvement was observed in the asphaltene reaction. Reducing the catalyst size significantly increased the degree of upgrading of all three materials. A kinetic model has been developed for the reaction and rate constants have been calculated.

ChemInform Abstract: Nucleophilic Addition of Silyl Enol Ethers to Aromatic Nitro Compounds: Scope and Mechanism of Reaction.

AbstractDie Durchführung der Titelreaktion an Nitrobenzol (IV) führt bevorzugt zu den ortho‐substituierten Produkten (II); mit den sterisch anspruchsvolleren Silylenolethern (Ia) und (Id) hingegen wird durch Substitution in para‐Stellung überwiegend (III) gebildet [vgl.

Nucleophilic addition of silyl enol ethers to aromatic nitro compounds: scope and mechanism of reaction

In sharp contrast to alkali-metal enolates, silyl enol ethers and ketene silyl acetals add to aromatic nitro compounds in the presence of a fluoride ion source to give the intermediate dihydroaromatic nitronates, which can be observed by NMR. In situ oxidation of the intermediate with bormine or DDQ yields a-nitroaryl carbonyl compounds in moderate-to-high yields. The reaction is applicable to alkyl-, alkoxy-, and halogen-substituted nitrobenzenes as well as to heterocyclic and condensed nitroaromatic compounds. While substitution ortho to the nitro group predominates with sterically undemanding silyl reagents, para-substitution products are exclusively obtained with bulky reagents. However, by blocking the para position with an appropriate group such as chlorine, the addition can be directed to the ortho position. Halogen atoms of halogenated nitroaromatics and p-nitrocumenyl chloride are not displaced in the reaction, suggesting the absence of radical ion intermediates. Dihydroaromatic nitro derivatives can be isolated in some cases, such as anthracene and naphthalene systems which are less prone to rearomatize. The use of silicon reagents in organic synthesis has been ex- panding rapidly in the past few year^,^-^ and versatile methods for carbon-carbon bond formations have been developed based on silyl enol ethers activated by fluoride ion sources. Various groups have reported alkylation^,^^^^ arylati~ns,~~ aldol conden- sation~,~ a~ylations,~ and Michael additions.&* Our own interest in this area originated with a notion that the nucleophilic reactivity of such reagent combinations might be distinctively different from that of the classical metal enolates and, in particular, that the enhanced nucleophilicity might be attained without significantly increasing basicity to lead to novel carbon-carbon bond-forming reactions. For example, we have reported (Scheme I) that tri- alkylketene silyl acetals can be added to a,@-unsaturated ketones in the presence of tris(dimethylamino)sulfonium difluorotri- methylsili~onate ~ (TASF) to give products equivalent to 1,4-ad- ditions of ester en~lates.~ This same reagent combination also initiates group-transfer polymerization of methacrylate mono- mers via sequential Michael additions* (Scheme I). In this paper, we wish to record our results on the fluoride-assisted addition of silyl enol ethers to aromatic nitro compounds. Oxidation of the resulting intermediate nitronate gives highly versatile a-nitroaryl