Annelated derivatives of 2-phenylquinoline, 2-(2′-pyridyl)quinoline and 2-phenyl-1,8-naphthyridine

Annelated derivatives of 2-phenylquinoline, 2-(2′-pyridyl)quinoline, and 2-phenyl-1,8-naphthyridine have been prepared where the bridging unit contains from one to four methylene units. The conformational properties of these molecules have been analyzed by ¹H nmr and uv spectroscopy as well as by pK_a determinations.     

Effect of the variation of swallow-tailed groups on the mesomorphic and electro-optical properties of chiral compounds derived from (S)-2-(6-hydroxy-2-naphthyl)propionic acid

Three homologous series of chiral swallow-tailed compounds, alkyl (S)-2-{6-[4-(4′-alkoxyphenyl)benzoyloxy]-2-naphthyl}propionates, (S)HNP(p,n,q) derived from (S)-2-(6-hydroxy-2-naphthyl)propionic acid in conjugation with a variety of swallow-tailed groups, attached to the external side of the chiral centre, have been synthesized and their mesomorphic and electro-optical properties studied. Both (S)HNP(p,1,2) and (S)HNP(p,1,3) exhibited an enantiotropic antiferroelectric SmC*_A phase. This implys that the swallow-tailed groups in the molecules favour zigzag pairing of the molecules in the smectic phase. The maximum P _S values of compounds (S)HNP(p,1,2) in the antiferroelectric phase were measured in the range 21–30 nC cm^-2; those of compounds (S)HNP(p,1,3) were in the range 15–23 nC cm^-2, indicating that these chiral compounds possess low polarity. The electro-optical response of the compounds in the antiferroelectric SmC*_A phase displayed thresholdless V-shaped switching.     

Preparation and characterization of symmetrical bis[4-chloro-2-pyrimidyl] dichalcogenide (S, Se, Te) and unsymmetrical 4-chloro-2-(arylchalcogenyl) pyrimidine: X-ray crystal structure of 4-chloro-2-(phenylselanyl) pyrimidine and 2-(p-tolylselanyl)-4-chloropyrimidine

Synthesis of a novel class of multinucleate pyrimidine chalcogen (S/Se/Te) derivatives has been successfully attempted for the first time by the selective substitution of chlorine at the C-2 position of 2,4-dichloropyrimidine with nucleophilic dichalcogenide anion E₂²⁻ (E = S, Se, Te) to afford bis[4-chloro-2-pyrimidyl] dichalcogenide. The highly electrophilic nature of 2,4-dichloropyrimidine compared to aryl chlorides has been further exploited to prepare a variety of 4-chloro-2-(arylchalcogenyl) pyrimidine compounds by substituting the chlorine exclusively at the C-2 position of 2,4-dichloropyrimidine with a variety of chalcogen bearing aryl anions ArE⁻ (Ar = phenyl, 1-naphthyl, p-tolyl, 4,6-dimethyl-2-pyrimidyl, 2-pyridyl, 4-methyl-2-pyridyl). All the newly prepared symmetrical and unsymmetrical pyrimidyl chalcogen compounds have been thoroughly characterized with the help of various spectroscopic techniques viz., NMR (¹H, ¹³C, ⁷⁷Se), FT-IR and mass spectrometry (in representative cases). The crystal structures of 4-chloro-2-(phenylselanyl) pyrimidine and 2-(p-tolylselanyl)-4-chloropyrimidine have been determined by X-ray crystallography.     

Absolute configuration of 2-methoxy-2-(2-naphthyl)propionic acid as determined by the 1H NMR anisotropy method

2-Methoxy-2-(2-naphthyl)propionic acid 1 and 2-hydroxy-2-(2-naphthyl)propionic acid 2 were prepared by the Grignard reaction of 2-naphthylmagnesium bromide with (1R,2S,5R)-(−)-menthyl pyruvate. The absolute configurations of (+)-1 and (+)-2 were determined to be S by the ¹H NMR anisotropy method.     

Optically active polymers containing side-chain photochromic moieties: Synthesis and chiroptical properties of copolymers of trans-4-(phenylazo)-1-naphthyl acrylate and trans-4-(1-naphthylazo)-phenyl acrylate with (?)-menthyl acrylate

The synthesis of photochromic optically active copolymers from trans-4-(phenylazo)-1-naphthyl acrylate (PANA), or trans-4-(1-naphthylazo)-phenyl acrylate (NAPA), and (?)-menthyl acrylate (MtA) is described. The copolymers prepared, having different contents of trans-phenylazonaphthalene moieties, have been characterized by IR, ¹H-NMR, UV, and GPC techniques. The chiroptical properties have been investigated by circular dichroism (CD) and the induced optical activity on the side-chain trans-phenylazonaphthalene chromophores discussed in terms of different conformational situations of the macromolecules in both the copolymer series. © 1994 John Wiley & Sons, Inc.     

Effects of Bis(aromatic) Pendants on Recognition of Nucleobase Thymine by Zn2+ -1,4,7,10-tetraazacyclododecane (Zn2+ -cyclen)

We have previously shown that the nucleobase thymine binding to Zn²⁺ -cyclen (cyclen=1,4,7,10-tetraazacyclododecane) complex became stronger by appending acridine, naphthalene, or quinoline rings to the cyclen. Amongst these, the pendant bis((1-naphthyl)methyl) or bis((4-quinolyl)methyl) groups yielded the most effective thymine-recognizing Zn²⁺ -cyclen complexes [J. Am. Chem. Soc., 121 (1999) 5426]. The present study was undertaken to find causes of the bis(aromatic) ring effect by X-ray crystal structure analysis and NMR studies. The crystal structure of the Zn²⁺ -bis((1-naphthyl)methyl)-cyclen complex with a deprotonated 1-methylthymine (1-MeT) failed to show the anticipated evidence for the double ~ - ~ stacking interactions between the two naphthalenes and the Zn 2+ -bound 1-MeT m (1-MeT m =N(3')-deprotonated 1-MeT). Crystal data: formula C₃₆ H₄₇ N₇ O₇ Zn, M r =755.19, monoclinic, space group P2₁/ c (No. 14), a =15.438(2) Å, b =14.093(3) Å, c =16.726(2) Å, g =90.53(1) V =3638.7(8) Å 3 Z =4, R =0.035, R _w =0.049. However, the ¹H NMR studies of Zn²⁼ -bis((4-quinolyl)methyl)-cyclen with 1-MeT in varying H₂O/CH₃ CN solution showed increasing upfield shifts of Me(5') and H(6') of the Zn²⁺ -bound 1-MeT in more aqueous media, indicating that the double intercalation with the two quinolines became more significant in more protic environments. We conclude that the double ~ - ~ stacking effect accounts for the enhanced recognition of thymine base by the appended bis((1-naphthyl)methyl) or bis((4-quinolinyl)methyl) groups.     

n-Butyl by-products in the syntheses of 2-(1- and 2-naphthyl)pyridines via lithiation

By-products in the syntheses of 2-(1- and 2-naphthyl)pyridines by successive treatments of 1- and 2-bromonaphthalenes with (a) n-butyllithium in ether and (b) pyridine are identified as 5-butyl-2-(1-naphthyl)pyridine and, tentatively, 5-butyl-2-(2-naphthyl)pyridine, respectively. It is proposed that these by-products result from reaction of intermediate compounds 1-lithio-2-naphthyl-1,2-dihydropyridines and 1-bromobutane.     

Synthesis of 1-(2-naphthyl)dihydro- and 1-(2-naphthyl)-2-thiodihydrouracils and their transformations

1-(2-Naphthyl)dihydro- and 1-(2-naphthyl)-2-thiodihydrouracils were obtained from N-(2-naphthyl)--alanine derivatives. The thiodihydrouracil was converted to a dihydrouracil. Bromination of 1-(2-naphthyl)dihydrouracil gave (1-bromonaphthyl)dihydrouracil. 1-(2-Naphthyl)-2-oxo-, 1-(2-naphthyl)-2-thio-. and 1-(1-bromo-2-naphthyl)-2-oxohexahydro-pyrimidines were obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii. No. 12, pp. 1695–1697, December, 1971.     

Synthesis and spectral properties of 2,3-dihydro-2-[(o- and p-substituted)anilinylidene]-1H-4-(p-methylphenyl)-7-[(o- and p-methyl)phenoxy]-1,5-benzodiazepines

A series of twelve new 2,3-dihydro-2-[(o- and p-substituted)anilinylidene]-1H-4-(p-methylphenyl)-7-[(o- and p-methyl)phenoxy]-1,5-benzodiazepines, which have potentially useful pharmacological properties, has been synthesized by condensing the 3,3-dimercapto-1-(p-methylphenyl)-2-propen-1-one with 3,4-diaminophenyl-R-phenyl ethers. Subsequently the 1H-1,5-benzodiazepine-2-thiones obtained were treated with the (o- and p-substituted)aniline. The structure of all products was corroborated by ir, ¹H nmr, ¹³C nmr and ms.     

Heterylation of 3-R1-5-R2-1,2,4-Triazoles with Derivatives of 3,5-Dinitro-1,2,4-Triazole

Heterylation of 3-R¹-5-R²-1'2'4-triazoles (pK _a 3-12) with N-alkyl-, N-alkenyl-, N-alkoxy-carbonyl-, N-oxoalkyl-, N-nitroxyalkyl, N-nitroaminoalkyl-3'5-dinitro-1'2'4-triazoles results insubstitution of a nitro group in 5 position of the dinitro compound yielding 1-R-methyl-3-nitro-5-(3-R¹-5-R²-1,2,4-triazolyl)-1,2,4-triazoles. The side processes: Hydroxide-ion attack on C⁵ and (or) N¹ of the ring both in the substrate and in the target compound afford 1-R-methyl3-nitro-1,2,4-triazol-5-ones, 3,5-dinitro-1,2,4-triazole and NH-acids of N-C-bitriazole series. Optimal reaction media are aprotic dipolar substances, and for compounds prone to heterolysis ethyl acetate-water systems. The azole pK _a is the decisive factor controlling the composition and the ratio of reaction products. The process is promising for azoles with pK _a > 5, and the optimal range of pK _a is 8-10.     

1-( p -Fluorophenyl)-2-(2′-pyridyl)ethanol and 1-( p -fluorophenyl)-2-(2′-pyridyl)ethene obtained from the condensation reaction of 2-picoline and p -fluorophenylaldehyde under catalyst-and solvent-free conditions

The novel intermediate 1-(p-fluorophenyl)-2-(2′-pyridyl)ethanol or 2-[2′-(1-hydroxy-1-(p-fluorophenyl)ethyl]pyridine and the corresponding novel dehydration compound 1-(p-fluorophenyl)-2-(2′-pyridyl)ethene or 2-[p-fluorophenylvinyl]pyridine were obtained from the condensation reaction of p-fluorophenylaldehyde and 2-picoline under catalyst-and solvent-free conditions. The intermediate 1-(p-fluorophenyl)-2-(2′-pyridyl)ethanol was obtained at 42 h reaction time and temperature of 120°C, respectively. ¹H-NMR, IR spectroscopic data of the 1-(p-fluorophenyl)-2-(2-pyridyl)ethanol clearly showed the presence of the-CH₂-CHOH-group. The compound was obtained as a white powder with m.p. 121–122°C and a yield of 8%. For 1-(p-fluorophenyl)-2-(2-pyridyl)ethene, the reaction conditions were similar, but the reaction temperature was increased to yield the double bond in the 1-(p-fluorophenyl)-2-(2′-pyridyl)ethene. At the reaction temperature of 140°C, the compound was a slightly brown powder with a m.p. of 78°C and yield of 18%. ¹H-NMR, IR spectroscopic data for the 1-(p-fluorophenyl)-2-(2′-pyridyl)ethene showed the presence of a double bond in trans configuration (-CH=CH-), characteristic of a styrylpyridine.     

Synthesis, spectroscopic properties and crystal structure determination of 2-(2-pyridin-4-yl-vinyl)-1H-benzimidazole derivatives

Substituted 2-(2-pyridin-4-yl-vinyl)-1H-benzimidazole derivatives 2, 3 and 6 were synthesized. 2-(2-Pyridin-4-yl-vinyl)-1H-benzimidazole 2 and 6-methyl-2-(2-pyridin-4-yl-vinyl)-1H-benzimidazole 3 were prepared by condensation reaction from 3-pyridin-4-yl-acrylic acid and corresponding 1,2-phenylenediamines in polyphosporic acid (PPA). 2,7,11-b-Triaza-benzo[c]fluorene 4 was prepared by photochemical dehydrocyclization reaction of ethanolic solution of 2-(2-pyridin-4-yl-vinyl)-1H-benzimidazole 2. 2-(2-Pyridin-4-yl-vinyl)-3H-benzimidazole-6-carbonitrile 6 was prepared by condensation reaction from 3-pyridin-4-yl-propenal and 4-cyano-1,2-phenylenediamine using p-benzoquinone as oxidants. The structure of novel benzimidazole derivatives has been studied by ¹H and ¹³C NMR, IR, MS, UV/Vis and fluorescence spectroscopy. The structure of 2-(2-pyridin-4-yl-vinyl)-1H-benzimidazole 2 was confirmed by X-ray single crystal structure analysis. The conformation of the molecule is E in regard to substituents position around vinyl double C=C bond. The non-planar molecules are mutually connected via the N–H···N and C–H···N type of intermolecular hydrogen bonds into infinite chains spreading along y axis.     

Synthesis and mass spectral fragmentation of 2-methylthio-7-(p-R-phenyl)-8-phenoxy-4,5-benzo-3-aza-2-nonem. III

A series of new 2-methylthio-7-(p-R-phenyl)-8-phenoxy-4,5-benzo-3-aza-2-nonem, IIIa, have been synthesized by regiospecific cycloaddition of phenoxyacetyl on to 2-methylthio-4-(p- R -phenyl)-3H-1,5-benzodiazepines IV. The structure was established by ir, ¹H-nmr and ms spectral data together with ¹³C-nmr spectral data of desulfurization products, VIa. Likewise, a study has been made of the fragmentation upon electron impact of IIIa and IV. All the spectra analyzed contain molecular ions and the principal fragmentation routes takes place either from the molecular ion or from m/e (M⁺ — 134) ion. This ion is the base peak for all the compounds analyzed.     

Structural Chemistry of Chiral Complexes. NMR and X-ray studies on Rh1 compounds of (S)-1-[bis(p-methylphenyl)phosphino]-2-[(p-methoxybenzyl)amino]-3-methylbutane

The Rh¹(diolefin)complexes [Rh(nbd)( 2 )][PF₆] [Rh(1,5-cod)( 2 )][PF₆], and [Rh((Z)-α -acetamidocinnamic acid)( 2 )][PF₆] ( 2 = the chiral P,N-ligand (S)-1-[bis(p-methylphenyl)phospino]-2-[p-methoxybenzyl)amino]-3-methylbutane have been prepared and characterized. These complexes exit as a mixture of isomers arising from different five-membered-ring conformations and diastereoisomers due to both the prochiral nitrogen and olefin ligands. The three-dimensional solutions structures of these complexes have been studied with the specific aim of understanding how the chiral pocket is built. Aspects of the exchange dynamics and their possible relevance to homogeneous hydrogenation are discussed The solid-state structure for the nbd complex, [Rh(nbd)( 2 )][PF₆], as well as detailed one- and two-dimensional ³¹P-, ¹³C-, and ¹H-NMR results are presented.     

3-Ferrocenyl-3-(1-naphthyl)cyclopropene. Synthesis, structure, and chemical transformations

Crystalline 3-ferrocenyl-3-(1-naphthyl)cyclopropene was prepared by dehydrobromination ofZ- andE-2-bromo-1-ferrocenyl-1-(1-naphthyl)-cyclopropanes by Bu^tOK in DMSO. The resulting compound and the startingZ-monobromocyclopropane were characterized by X-ray diffraction analysis. The obtained cyclopropene reacts with 1,3-diphenylisobenzofuran to give a [4+2]-cycloadduct. The small ring opens upon treatment with HBF₄ etherate to afford isomericZ- andE-prop-1-enes and 1-ferrocenyl-3H-benzo[e]indene. Thermolysis of this cyclopropene results in the formation of 1-ferrocenyl-9bH-benzo[e]indene. In all cases, opening of the small ring is accompanied by exclusive alkylation of the naphthalene moiety. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 499–506, March, 1998.     

1H and 13C NMR study of the conformations of the atropisomers of some 1-(11-naphthyl)-2,4-dioxo-(or 2-thio-4-oxo)-hexahydro-pyriminides

The ¹H and ¹³C NMR spectra of the atropisomers of 6-(or 5-)-methyl-1-(1¹-naphthyl)-2, 4-dioxo-(or 2-thio-4-oxo)-hexahydro-pyrimidines, 1 to 4, are assigned on the basis of NOE and double resonance experiments. The syn-anti configurations of the isomers of 6-methyl-2,4-dioxo-pyrimidine follow from the close similarity of the NMR parameters to those observed with the isomers of the 6-methyl-2-thio derivative of known configuration. That of the 5-methyl derivatives was assigned from NOE and magnetic anisotropy effects of the naphthalene ring and of the (thio) amide group. Allylic strain between the naphthyl and 5-methyl groups makes the axial confomation prefered int he anti isomers. In the syn isomers, however, the equational and axial conformations are approximately equally populated, apparently due to interference between the remote benzene ring and the axial methyl group. The equatorial conformation is prepared with the 5-methyl derivatives.     

Synthesis and spectral properties of 2-methylthio-3H-4-(para-substituted-phenyl)-7-[(o-, and p-substituted)-phenylthio]-1,5-benzodiazepines

A series of twelve new 2-methylthio-3H-4-(p-substituted phenyl)-7-[(o-, and p-substituted)phenylthio]-1,5-benzodiazepines, which have potentially useful pharmacological properties, has been synthesized by condensing the 3,3-dimercapto-1-(para-substituted-phenyl)-2-propen-1-one with 3,4-diamino phenyl-R-phenylthio ethers, and subsequently the 1H-1,5-benzodiazepine-2-thiones obtained were treated with sodium hydride and methyl iodide. The structure of all products was corroborated by ir, ¹H-nmr, ¹³C-nmr and ms.     

Pyrimidine derivatives. IV. Synthesis of N1 -(2-methoxy-4-pyrimidyl)sulfaniiamide

N¹-(2-Methoxy-4-pyrimidyl)sulfanilamide was successfully prepared through three alternative routes. Namely, the above compound was obtained by condensation of 4-amino-2-methoxy-pyrimidine (III) with p-acetaminobenzenesulfonyl chloride and p-nitrobenzenesulfonyl chloride and by direct condensation with sulfanilamide.     

Novel Copolymers of 4-Fluorostyrene. 11. Some Ring-substituted 1,1-dicyano-2-(1-naphthyl)ethylenes

Novel copolymers of trisubstituted ethylene monomers, ring-substituted 1,1-dicyano-2-(1-naphthyl)ethylenes, RC₁₀H₆CH?C(CN)₂ (where R is H, 2-OCH₃, 4-OCH₃) and 4-fluorostyrene were prepared by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, ¹H and ¹³C-NMR. The order of relative reactivity (1/r ₁) for the monomers is (5.86) > 2-CH₃O (4.28) > 4-CH₃O (2.87). Relatively high T_g of the copolymers in comparison with that of poly(4-fluorostyrene) indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (7.3–7.7% wt.), which then decomposed in the 500–800°C range.     

Complexes of 2-(2-hydroxyacetophenone)imino-5-(p-anisyl)-1,3,4-oxadiazole with some bivalent metals ions

Summary The metal complexes of the type [M(SB)₂(H₂O)₂] and [M(SB)₂][where M = Mn^II, Co^II, Ni^II or Cu^II, M = Zn^II Cd^II, Hg^II and Pb^II and SBH = 2-(2-hydroxyacetophenone)imino-5-(p-anisyl)-1,3,4-oxadiazole] have been prepared and characterised by elemental analyses, thermal analyses, magnetic measurements, electronic and infrared spectral studies. The complexes [M(SB)₂(H₂O)₂] possess octahedral structures, whereas complexes [M(SB)₂] are tetrahedral. The crystal field parameters of the Co^II and Ni^II complexes are also calculated.