- Energy transfer in bichromophoric molecules: The effect of symmetry and donor/acceptor energy gap
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The dependence of the rate of singlet excitation transfer on the donor-acceptor energy gap was investigated in bichromophoric spiranes with symmetry-forbidden zero-order electronic coupling. The fluorescence measurements were performed in a supersonic jet in order to avoid collisional and inhomogeneous line broadening. Fluorescence excitation spectra and single-vibronic-level emission spectra of the model chromophores cyclopentaphenanthrene and 1,8-dimethylnaphthalene and the bichromophores spirofluorenephenanthrene and spirofluorenenaphthalene are presented and analyzed. Although the transition moments of the linked chromophores are rigorously perpendicular and the exchange coupling between the v′ = 0 states is computationally shown to be zero, all spiranes with energy gaps larger than ～1000 cm-1 exhibited complete electronic energy transfer from all vibrational states of the electronically excited donor, including the undistorted v′ = 0 state. This behavior is explained in terms of vibronic coupling between the sparse states of the donor and the dense manifold (pseudocontinuum) of the acceptor states. The electronic energy transfer was sufficiently fast to result in measurable lifetime broadening of the donor absorption lines, from which the kEET was estimated. The results demonstrate that the zero-order picture overestimates the degree of the molecular orbital symmetry control over electronic energy transfer and charge-transfer rates and that at sufficiently high driving forces the vibronically mediated "symmetry-forbidden" electronic energy transfer can be very rapid (～1 × 1012 s-1).
- Yip,Levy, Donald H.,Kobetic, Renata,Piotrowiak, Piotr
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- Synthesis of anti-4,5,14,15-Tetramethyl2>(2,7)naphthalenophane-1,11-diene and its Dianion. ESR and ENDOR Studies of its Radical Anion and Other Related Radical Ions
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A synthesis of anti-4,5,14,15-tetramethyl2>(2,7)naphthalenophane-1,11-diene (4) has been achived in ten steps from 1,8-naphthalic anhydride in an overall yield of 4percent.The key step in the synthesis employed a double-barreled sulfur analogue of the Sommelet-Hauser rearrangement.Unexpectedly, formation of the dianion and radical anion of 4 occured without intramolecular cyclization.The radical anions and the radical cations both of 4 and of anti-4,5,14,15-tetramethyl2>(2,7)naphthalenophane (19) have been characterized by ESR and ENDOR spectroscopy.
- Rohrbach, William D.,Gerson, Fabian,Moeckel, Reinhart,Boekelheide, Virgil
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- EVIDENCE FOR THE EXISTENCE OF PEROXONIUM INTERMEDIATES
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Low temperature 1H and 2H nmr are consistent with the presence of peroxonium intermediates in the intramolecular alkylation of two different bromoperoxides.In one case decomposition of this peroxonium intermediate results in unusual heterolytic oxygen-oxygen bond cleavage and methyl migration.
- Mitchell, John C.,Heaton, Simon,Porter, Ned A.
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- Unique behavior of 2,6-bis(bromomethyl)naphthalene as a highly active organic DNA crosslinking molecule
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Among 14 bis-halomethylated naphthalenes and quinolines, 2,6-bis(bromomethyl)naphthalene was found to have highly active crosslinking activity on DNA. The unique behavior of high microbial mutagenicity, even though it had a low propensity to form double-strands in linearized plasmid DNA, suggested that it would offer a new seed, capable of forming intrastrand crosslinks similar to cisplatin. The electron withdrawal extent of the halogen atoms, the substitution patterns of two halomethyl groups, and the introduction of a nitrogen atom into the aromatic nucleus had remarkable effects on the activity of the molecule.
- Higashi, Toshinori,Uemura, Koichi,Inami, Keiko,Mochizuki, Masataka
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- Eight-membered-ring diaminocarbenes bearing naphthalene moiety in the backbone: DFT studies, synthesis of amidinium salts, generation of free carbene, metal complexes, and solvent-free copper catalyzed azide-alkyne cycloaddition (CuAAC) reaction
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A new type of eight-membered ring N-heterocyclic carbene (NHC) bearing a rigid naphthalene moiety in the backbone is reported for the first time. Stereoelectronic properties of 4,5-dihydro-1H-naphtho[1,8-ef][1,3]diazocin-3(2H)-ylidene (NaphtDHD) and small
- Chesnokov, Gleb A.,Topchiy, Maxim A.,Dzhevakov, Pavel B.,Gribanov, Pavel S.,Tukov, Aleksandr A.,Khrustalev, Victor N.,Asachenko, Andrey F.,Nechaev, Mikhail S.
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supporting information
p. 4331 - 4345
(2017/04/03)
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- 1-Aminobenzocyclobutene-1-phosphonic Acid and Related Compounds as Inhibitors of Phenylalanine Ammonia-Lyase
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Five new geminal aminocycloalkanephosphonic acids (4 – 8) containing both an aromatic ring and a cycloalkane ring were synthesized and evaluated as potential inhibitors of buckwheat phenylalanine ammonia-lyase (PAL). Within the set of compounds which are related to 2-aminoindane-2-phosphonic acid (AIP, 3), a known powerful inhibitor of PAL, racemic 1-aminobenzocyclobutene-1-phosphonic acid (4), was six times weaker than AIP as an in vitro inhibitor of buckwheat PAL, but six times stronger than AIP as an in vivo inhibitor of phenylalanine-derived anthocyanin synthesis in buckwheat.
- Zoń, Jerzy,Miziak, Piotr
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- Synthesis and properties of dicarboximide derivatives of perylene and azaperylene
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The N-alkyl dicarboximide derivatives of naphthylisoquinoline and binaphthalene were prepared by the hetero coupling reaction of the corresponding N-alkyl dicarboximide derivatives of stannylnaphthalene with bromodimethyisoquinoline and bromodimethylnaphthalene, respectively. The ring closing of the N-hexyl derivatives of naphthylisoquinoline and binaphthalene produced the N-hexyldicarboximide derivatives of azaperylene and perylene having the same substituents, respectively. The absorption spectra and fluorescence spectra of the azaperylene and perylene derivatives were investigated.
- Nagao, Yukinori,Yoshida, Tatsurou,Arimitsu, Koji,Kozawa, Kozo
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experimental part
p. 1197 - 1213
(2010/10/04)
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- Secondary interactions in crystals of all ten isomers of Di(bromomethyl)naphthalene
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The packing of all ten isomers of di(bromomethyl)naphthalene is analysed; nine of the structures were determined here, one (the 1,8-isomer) was already known. The 1,5- and 2,6-isomers display crystallographic inversion symmetry and the 2,7-isomer mirror symmetry through the central bond. For the 1,2-, 1,7- and 2,7-isomers, the bromomethyl groups point to the same side of the ring system, and for all other isomers to opposite sides. As expected, the molecules are linked into aggregates by various types of interactions: weak hydrogen bonds CH...Br, Br...Br interactions, CH...π contacts, π ...π stacking and Br...π contacts. The weak hydrogen bonds tend to be numerous but relativelyi; long, and do not combine to form readily recognisable patterns; a more readily assimilated view of the packing is based on the Br...Br interactions, which are observed for all isomers except 1,7 and 2,3, and in some cases lead to aggregation to form quadrilaterals or chains. With decreasing frequency, the interactions π ...π, C-H...π and Br...π are observed, but the latter are rare (just two examples) and very asymmetric, with contacts to only one or two carbons.
- Jones, Peter G.,Kus, Piotr
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experimental part
p. 433 - 444
(2010/10/01)
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- A novel fluoride ion colorimetric chemosensor
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(Figure Presented) A novel phosphonium derivative of naphthalene was synthesized by the reaction of 1,8-dibromomethylnaphthalene with triphenylphosphine, which only showed a distinct color change when treated with fluoride ions.
- Hyoung, Min Yeo,Byung, Ju Ryu,Kye, Chun Nam
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supporting information; scheme or table
p. 2931 - 2934
(2009/04/18)
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- Mononuclear and polynuclear chain complexes of a series of multinucleating N/S donor ligands
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We have prepared a series of five ligands with potentially N,S-bidentate chelating arms derived from 3-[2-(methylsulfanyl)phenyl]pyrazole linked to central aromatic spacers by methylene units. Complexes with a variety of architectures have been obtained, including simple mononuclear complexes and polynuclear chain complexes. The p-xylyl-spaced ligand L1 forms one-dimensional helical coordination polymers with copper(I) and silver(I) ions. These polymers display interligand aromatic stacking interactions within each helical chain. The m-xylyl-spaced ligand L2 forms a coordination polymer with copper(I) but a mononuclear complex with the larger silver(I) ion in which the central phenyl ring is involved in an η1 π-type Ag...C interaction with the AgI. The 3,3′-biphenyl-spaced ligand L3 also forms one-dimensional polymers with silver(I) and copper(I) ions, but in this case the sequence of bridging ligands between one metal centre and the next follows a zig-zag path rather than being helical. The 1,8-naphthyl-spaced ligand L4 only forms mononuclear complexes with copper(I) and silver(I) ions showing that this spacer is not large enough to enforce a bridging coordination mode. The three-armed ligand L5, prepared from 2,4,6-tris-(bromomethyl)mesitylene, also forms a mononuclear complex with silver(I) ions, where one of the three arms is pendant. However, when excess silver(I) ions are present two of these mononuclear complexes can be assembled into the trinuclear complex [Ag3(L5) 2] (ClO4)3. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.
- Ronson, Tanya K.,Adams, Harry,Ward, Michael D.
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p. 4533 - 4549
(2007/10/03)
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- Photolytic, thermal, addition, and cycloaddition reactions of 2-diazo-5,6- and -3,8-disubstituted acenaphthenones
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Preparation and varied thermal and photolytic reactions of 2-diazo-5,6-(disubstituted)acenaphthenones (11a-d) and 2-diazo-3,8- dimethoxyacenaphthenone (12) are reported. Alcohols react thermally and photolytically with 11a-c with losses of N2 to yield 2-alkoxynaphthenones (24a,b and 47a,b) and acenaphthenones (25 and 48a,b). Aniline and diphenylamine are converted by 11a-c at 180°C to acenaph[1,2-6]indoles (29a,b and 53a,b). Thermolyses of 11a-c at ～450°C (0.15 mmHg) yield reduction products 25 and 48a,b, respectively. Wolff rearrangements to 1,8-naphthyleneketenes (15a-d) and/or their derivatives are not observed in the above experiments. Oxygen converts 11a-c thermally to acenaphthenequinones (19a-c) and/or 1,8-naphthalic anhydrides. Insertion, addition, substitution, and/or isomerization reactions occur upon irradiation of 2-diazoacenaphthenones in cyclohexane, benzene, and tetrahydrofuran. Photolysis of 11d in benzene in the presence of O2 yields the insertion-oxidation product 2-hydroxy-5,6-dinitro-2-phenylacenaphthenone (60). Photolyses of 11a-c in nitriles result in N2 evolution and dipolar cycloaddition to give acenaph[1,2-d]oxazoles (41 and 61a,b). Acetylenes undergo thermal and photolytic cycloaddition/1,5-sigmatropic rearrangement reactions with 11a-d with N2 retention to give pyrazolo[5,1-a]quinolin-7-ones (69f-j). 2-Diazoacenaphthenones 1a and 11a react thermally and photolytically with electronegatively-substituted olefins with N2 expulsion to yield (E)- and (Z)-2-oxospiro[acenaphthylene-1(2H),1′cyclopropanes] 73a-c and 74a-c, respectively. The mechanisms of the reactions of la, 11a-d, and 12 reported are discussed.
- Blair, Patricia A.,Chang, Sou-Jen,Shechter, Harold
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p. 7123 - 7133
(2007/10/03)
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- New multidentate pyrazolyl-pyridine ligands - Synthesis and structures
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Five new multidentate ligands have been prepared containing N,N-bidentate pyrazolyl-pyridine units linked to a central aromatic spacer unit. The ligands 3,3′-bis(3-{pyridin-2-yl}-pyrazol-1-yl-methyl)-p-terphenyl (I), 4,4′-bis(3-{pyridin-2-yl}-pyrazol-1-yl
- Bell, Zoee R.,McCleverty, Jon A.,Ward, Michael D.
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p. 665 - 670
(2007/10/03)
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- Highly enantioselective and practical cinchona-derived phase-transfer catalysts for the synthesis of α-amino acids
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A new class of naphthalene-based dimeric cinchona alkaloids 1 are very efficient and practical phase-transfer catalysts in the alkylation of a glycine derivative. The mild reaction conditions and the high catalytic efficiency (high yields and ee values) could make these alkaloids practical catalysts in the industrial synthetic process for natural and nonnatural chiral α-amino acids.
- Park, Hyeung-Geun,Jeong, Byeong-Seon,Yoo, Mi-Sook,Lee, Jeong-Hee,Park, Mi-Kyoung,Lee, Yeon-Ju,Kim, Mi-Jeong,Jew, Sang-Sup
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p. 3036 - 3038
(2007/10/03)
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- Reductive cleavage of benzannelated cyclic ethers and amines: Synthetic applications
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Reduction of symmetrical intramolecular diarylmethyl ethers (3a and 8a) and amines (3b and 8b) with alkali metals in THF allows the generation of unsymmetrical oxy- or amino-functionalised arylmethyl organometallics. Such intermediates were successfully trapped with various electrophiles, allowing a new access to unsymmetrically 2,2'-disubstituted-1,1'-biaryls (5aa-5bf) and 1,8-disubstituted naphthalenes (10aa-10be). (C) 2000 Elsevier Science Ltd.
- Azzena, Ugo,Demartis, Salvatore,Pilo, Luciano,Piras, Elisabetta
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p. 8375 - 8382
(2007/10/03)
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- Oligosaccharide analogues of polysaccharides. Part 19. Synthesis of 2- (naphthalen-1-yl)ethyl cellooligoglycosides and [(naphthalene-1,8- diyl)di(ethane-2,1-diyl)] bis[cellooligoglycosides]
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Glucosyl, cellobiosyl, cellotriosyl, cellotetraosyl, and cellooctaosyl residues were attached to naphthalene-1,8-diethanol (3) with the goal of preparing mimics of cellulose I. Among the templates that were considered, 1,8-diethynylnaphthalene (1) led to unstable products, and glycosidation of naphthalene-1,8-dimethanol (2) gave orthoesters that could not be rearranged to glycosides (Scheme 1). The conformation of 3 in the crystal and of its dimethyl ether 14 in solution was studied by X-ray analysis and force-field calculation (Figs. 1-3). Rotation around the Ar-CH2 and CH2-CH2 bonds of 14 is only weakly hindered and the O···O distance of crystalline 3 (6.01 A) corresponds to the mean distance of the parallel chains of cellulose I(β). The acetylated glycosyl bromides 18 and 19 were prepared by a new convergent synthesis (Scheme 2). Glycosylation of 3 by the glycosyl bromides 15-19 under established conditions of the Koenigs-Knorr reaction proved problematic, particularly on account of an acetyl transfer blocking one of the hydroxyethyl groups. Basic zinc carbonate, however, promoted glycosylation of 12 and 3 by the glycosyl bromides 15-19 and did not lead to transacetylation (Scheme 3). The mono- to tetrasaccharides 32-35 and 42-45 were isolated in yields of 5682%, and the octasaccharides 36 and 46 in 32 and 16%, respectively. The mono- and disaccharides 32, 33, 42, and 43 were deacetylated with NaOMe in MeOH. Aqueous NaOH was used for the tri-, tetra-, and octasaccharides 34-36 and 44-46, as their partially deacetylated derivatives proved insoluble in MeOH. The fully deprotected saccharides 37-41 and 47-50 were isolated in over 90%, while the yield of the dioctaoside 51 was lower on account of its poor water solubility.
- Xu, Jinwang,Vasella, Andrea
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p. 1728 - 1752
(2007/10/03)
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- 7-Spiroindanyl derivatives of naltrexone and oxymorphone as selective ligands for δ opioid receptors
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A series consisting of spiroindanyl (5-7), benzospiroindanyl (8-10), and spiroperinaphthyl (11) derivatives of naltrexone and oxymorphone were synthesized in order to investigate the role of an orthogonal-oriented 'address' for δ opioid receptors. All of
- Ohkawa,DiGiacomo,Larson,Takemori,Portoghese
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p. 1720 - 1725
(2007/10/03)
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- Laser flash photolysis of 1,8-bis(substituted methyl)naphthalenes
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The transient absorption spectra obtained by the laser flash photolysis of 1,8-bis(substituted methyl)naphthalenes have been measured.By comparison with the transient spectra for 1-(substituted methyl)naphthalenes, the transient species absorbing at 430 nm observed from (PhO-CH2)2Naph is attributed to the triplet state.In the case of (PhS-CH2)2Naph, absorption bands at 490 and 430 nm due to PhS are observed in addition to an absorption band in the region of 310-400 nm, which is due to the carbon-centred radical CH2Naph(CH2-SPh)>.For (PhSe-CH2)2Naph, a new broad absorption band appeared in the region of 400-520 nm, which covered weak absorption bands due to PhSe at 430 and 490 nm.The new absorption is attributed to the carbon-centred radical CH2Naph(CH2-SePh)> in which there is considerable interaction between the CH2- and PhSe moieties.The possibility of a bridged radical for CH2Naph(CH2-SePh) is suggested by MO calculations.
- Ouchi, Akihiko,Koga, Yoshinori,Alam, Maksudul M.,Ito, Osamu
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p. 1705 - 1710
(2007/10/03)
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- SPIROINDANE OPIATE ANALOGS
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The present invention provides biologically active compounds of the formulas (I) and (II): (* CHEMICAL STRUCTURE *) (I) (* CHEMICAL STRUCTURE *) (II) wherein R3 is H or a hydroxyl protecting group, R2 is OH, H or a protected hydroxyl group, R1 is alkyl, c
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- Synthesis of Crown Ethers That Geometrically Orient Cations Relative to a Naphthalene ? System. A Look at the Equilibration of Enantiomeric Conformations by "Rope-Skipping" Crown Ethers
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A number of new naphthalene crown ethers were synthesized in moderate yield from the appropriate bis(halomethyl)naphthalenes and polyethylene glycols.The following crown ethers were synthesized: 2,3-naphtho-14-crown-4 (15percent), 2,3-naphtho-17-crown-5 (19percent), 2,3-naphtho-20-crown-6 (36percent), 1,8-naphtho-15-crown-4 (20percent), 1,8-naphtho-18-crown-5 (7percent), 1,8-naphtho-21-crown-6 (38percent), 1,2-naphtho-20-crown-6 (4percent), 1,5-naphtho-22-crown-6 (14percent), 1,5-naphtho-19-crown-5 (11percent), 1,4-naphtho-22-crown-6 (9percent), 1,3-naphtho-21-crown-6 (16percent).These crown compounds form a series in which complexed cations perturb the naphthalene ? system from different directions.Experimental evidence concerning the ease of equilibration of enantiomeric conformations by "rope-skipping" crown ethers is also reported.The equilibration of 1,5-naphtho-22-crown-6 enantiomeric conformations has about a 6.3-kcal energy of activation, while the corresponding barrier for 1,5-naphtho-19-crown-5 is greater than 21 kcal.
- Brown, Houston S.,Muenchausen, Chrysa P.,Sousa, Lynn R.
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p. 1682 - 1686
(2007/10/02)
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- Synthesis of Potentially Basic Hydrocarbons by Sulphur Extrusion and/or Bis-Wittig Reactions. Two Syntheses of Benzindenophenalene and a New Synthesis of Dibenzonaphthacene (Zethrene)
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Macrocyclic bis-sulphides have been prepared from 1,2-, 2,3-, and 1,8-bis(bromomethyl)naphthalenes.Methylation of the bis-sulphides, followed by the Stevens rearrangement, gave the corresponding carbocycles with extra-annular sulphide groups; removal of these sulphide groups by Hofmann elimination led to spontaneous trans-annular condensation.Using this general method, two hydrocarbons were synthesized: benzindenophenalene and dibenzonaphthacene (or zethrene).An alternative synthetic route led to the synthesis of benzindenophenalene, using the Wittig reaction between naphthalene-2,3-carbaldehyde and 1,8-bis(triphenylphosphoniomethyl)naphthalene dibromide.
- Kemp, William,Storie, Iain T.,Tulloch, Charles D.
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p. 2812 - 2817
(2007/10/02)
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