- STRUCTURAL STUDY ON 1-PHENYL- AND 1-(2-NAPHTHYL)-8-TROPYLIONAPHTHALENE HEXAFLUOROANTIMONATES
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The molecular structures of 1-phenyl- (5) and 1-(2-naphthyl)-8-tropylionaphthalene (6) hexafluoroantimonates were determined by x-ray crystallography and compared with those of 1,8-diphenylnaphthalene and related compounds.In these compounds, the two aromatic substituents face each other in a nearly parallel conformation with a splayed-out arrangement.In the cations 5 and 6, the distance between the facing rings is appreciably shorter than that of other 1,8-diarylnaphthalenes, suggesting the presence of some attractive force.This attraction is ascribed to an intramolecular charge-transfer interaction, and seems to bring about a slight inward bending of the 2-naphthyl substituent in the cation 6.AM1 calculations were carried out for these cations and the results are discussed in comparison with the results of x-ray crystallography.
- Tsuji, Ryotaro,Komatsu, Koichi,Takeuchi, Ken'ichi,Shiro, Motoo,Cohen, Shmuel,Rabinovitz, Mordecai
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- Synthesis of axially chiral 1,8-diarylnaphthalene ligands and application in asymmetric catalysis: An intriguing fluorine effect
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A fluorinated and a non-fluorinated axially chiral 1,8-diarylnaphthalene ligand have been synthesized through an Ullmann and Suzuki coupling reaction based strategy. A practical methodology for the successful chiral resolution of the newly synthesized catechol based moiety is presented. We also disclose the preliminary application of these axially chiral molecules as ligands in asymmetric transformation reactions.
- Ghosh, Harisadhan,Vavilala, Ravishashidhar,Szpilman, Alex M.
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- Exploring the selectivity of the Suzuki-Miyaura cross-coupling reaction in the synthesis of arylnaphthalenes
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A series of 1-arylnaphthalenes and 1,8-diarylnaphthalenes were synthesized by the Suzuki-Miyaura cross-coupling methodology showing significant differentiation in the yields and selectivity between aryl rings with electron donating (higher yields), and el
- Lima, Carlos F.R.A.C.,Rodriguez-Borges, José E.,Santos, Luís M.N.B.F.
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experimental part
p. 689 - 697
(2011/03/19)
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- Synthesis and molecular structure of symmetrical 1,8-diarylnaphthalenes
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The synthesis of substituted 1,8-diarylnaphthalenes is reported. A bis-Suzuki coupling strategy starting from 1,8-dibromonaphthalene provides a useful and general route to the 1,8-diarylnaphthalene scaffold. In this context, N-heterocyclic benzhydrylamine ligands, in combination with PdCl2, were found to form especially efficient catalytic systems. The syn/anti ratios were determined in solution from their 1H NMR spectra. Analysis of the molecular structure in the solid state for six new targets focused on deformation of the naphthalene core. The observed lack of planarity occurs as a result of several parameters, such as the nature and number of substituents, the substitution pattern as well as steric congestion and π-stacking between cofacial rings. The synthesis of substituted 1,8-diarylnaphthalenes using bis-Suzuki coupling of 1,8-dibromonaphathalene is described. Molecular structures in the solid state for six new compounds were analyzed. The influence of several parameters on naphthalene core deformation are described.
- Pieters, Gregory,Terrasson, Vincent,Gaucher, Anne,Prim, Damien,Marrot, Jerome
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experimental part
p. 5800 - 5806
(2011/01/12)
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- Synthesis of a sterically crowded atropisomeric 1,8-diacridylnaphthalene for dual-mode enantioselective fluorosensing
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An efficient synthetic route to a sterically crowded 1,8- diheteroarylnaphthalene-derived enantioselective fluorosensor that operates in two different detection modes utilizing fluorescence lifetime and intensity has been developed. Screening of palladium-catalyzed Negishi, Kumada, Suzuki, Hiyama, and Stille coupling methods showed that the latter affords highly congested 1,8-diarylnaphthalenes in superior yields. Despite severe steric hindrance, axially chiral 1,8-bis(3-(3′,5′-dimethylphenyl)-9- acridyl)naphthalene, 1, was obtained in 68% yield from 1,8-dibromonaphthalene, 14, and 3-(3′,5′-dimethylphenyl)-9-tributyl-stannylacridine, 13, via two consecutive Stille cross-coupling steps using tetrakis(triphenylphosphine)- palladium(0) as catalyst in the presence of copper(II) oxide. The preparation of 1 involved formation of 4-(3′,5′-dimethylphenyl)-2-chlorobenzoic acid, 7, through microwave-assisted Suzuki coupling of 4-bromo-2-chlorobenzoic acid, 10, and 3,5-dimethylphenylboronic acid, 11, followed by regioselective amination with aniline and acridine ring construction in phosphorus oxybromide. Lithiation, subsequent treatment with trimethylstannyl chloride, and Stille cross-coupling then completed the five-reaction sequence providing 1 in 57% overall yield. The enantiomers of 1 were separated by semipreparative HPLC on a (R,R)-Whelk-O 1 column and successfully employed in enantioselective fluorosensing of N-t-Boc-protected serine, 20, glutamine, 22, proline, 23, and 2-hydoxy-2-methylsuccinic acid, 21. Fluorescence titration experiments with 23 revealed that both static and dynamic quenching occur with distinctive enantioselectivity. Addition of (R)-23 to a solution of (+)-1 in acetonitrile resulted in stronger fluorescence quenching than titration with the (S)-enantiomer of 23. The fluorescence lifetime, τ, of 1 was determined as 18.8 ns and steadily decreased to 7.5 and 6.8 ns in the presence of 0.1 M of (S)-23 and (R)-23, respectively.
- Mei, Xuefeng,Martin, Rhia M.,Wolf, Christian
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p. 2854 - 2861
(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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- A cyclic oligophenylene containing two 1,8-naphthalene units bridged by two face-to-face biphenyl linkages exhibiting unusual strain and π-π interaction
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equation presented Strong π-π interaction 1,8-[1,8-Naphthalenediylbis(4′,4-biphenyldiyl)]naphthalene, a very stable strained cyclophane, has been synthesized in moderate yield using the copper-catalyzed coupling of 1,8-bis(4-(tributylstannyl)phenyl)naphth
- Iyoda, Masahiko,Kondo, Terumasa,Nakao, Kazumi,Hara, Kenji,Kuwatani, Yoshiyuki,Yoshida, Masato,Matsuyama, Haruo
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p. 2081 - 2083
(2007/10/03)
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- Steric Effects. Internal Rotation of 1-Aryl-8-phenylnaphthalenes
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A general, albeit low-yielding, synthesis of 1-aryl-8-phenylnaphthalenes was devised and used to prepare three 1-(3'-X-5'-isopropylphenyl)-8-phenylnaphthalenes (X = H, F, Br).Activation parameters for the rotation of the 3'-X-5'-isopropylphenyl group were
- Cosmo, Robert,Sternhell, Sever
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p. 1107 - 1126
(2007/10/02)
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- Preparation and Conformational Properties of Several 1,8-Diarylnaphthalenes
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Six new 1,8-diarylnaphthalenes, each having closely held parallel aromatic rings, were synthesized by a Kharash-type Grignard cross-coupling of arylmagnesium iodide and 1,8-diiodonaphthalene in the presence of N,N'-bis(1-methyl-3-oxobutylidene)ethylenediaminatonickel(II) as a catalyst.Among them, 1,8-di(1-naphthyl)naphthalene was obtained as cis and trans rotamers, caused by the restricted rotation at the 1,8-position.Interconversion between the rotamers on heating above their melting points was confirmed by differential scanning calorimetry.The proton magnetic resonance spectral studies of the 1,8-diarylnaphthalenes indicated the presence of a face-to-face arrangement of aromatic rings in the peri-position.Two new 8,8'-diaryl-1,1'-binaphthyls, each having two sets of closely held parallel aromatic rings, were isolated as minor coupling products.Trans-trans conformations were proposed for them on the basis of their thermal behavior.Several nickel(II) complexes were found to be effective catalysts for preparative Grignard cross-coupling reaction involving closely crowded geometry.
- Ibuki, Eiichi,Ozasa, Shigeru,Fujioka, Yasuhiro,Mizutani, Hiroshi
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p. 845 - 851
(2007/10/02)
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