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A new dimer of natural isoflavonoid along with some known flavonoid compounds was successfully isolated from the roots of Indonesian Sesbania grandiflora plant using ethyl acetate extraction. The new compound specified as naturally bi-isoflavonoid with (4→6) inter-isoflavanyl linkage and four known flavonoids xenognosin B, liquiritigenin, 7,2′4′-trihydroxyisoflavone, demethylvestitol, and 1,1′-bi-2-naphthol was isolated and the antituberculosis activity of the compounds was studied. The structure of all compounds was elucidated with the aid of 1D and 2D NMR, UV spectroscopy, and HRESI mass spectrometry. The data obtained were also compared with the previous published data. Among compounds, 1,1′-bi-2-naphthol was found to exhibit the highest activity against Mycobacterium tuberculosis H37Rv with the MIC's value of 10.9 µM while the biisoflavonoid with (4→6) inter-isoflavanyl linkage showed moderate activity with the MIC's value of 92.2 nM, compared with isozianid as a positive control with the MIC's value of 0.569 nM. It is worth to note that 1,1′-bi-2-naphthol and biisoflavonoid with (4→6) inter-isoflavanyl linkage were isolated for the first time from a natural source. Both compounds have been previously reported as synthetic compounds, which is synonymous with 3,4- trans-4-[(3S)-7,2′-dihydroxy-4′-methoxyisoflavan-6-yl]-7,2′-dihydroxy-4′-methoxyisoflavan and 1,1′-bi-2-naphthol, respectively. In this respect, the results of this study suggest that the roots of S. grandiflora is a potential source of new natural product compounds, with promising bioactivities. [ABSTRACT FROM AUTHOR]

A series of novel circularly polarized luminescence (CPL) active liquid crystal materials ( R -BIN-OC and R -BIN-NC) were prepared by covalent-linking of R -binaphthol and cyanostilbene (CS) via either an ester or an amide. The effects of covalent bond structure with liquid crystal property, optical behavior, and chiroptical response were systematically evaluated. The results revealed that R -BIN-OC and R -BIN-NC can be self-assembled to form the columnar liquid crystal, and their phase transition temperatures were remarkably increased with the increase of the conjugation effect, accompanied by the expansion of the liquid crystal range. Importantly, they presented higher fluorescence performance with Φ F values of 26 % and 34 % in the solid-state, respectively. Moreover, the chiral of R -binaphthyl was effectively transferred to the CS fluorophore through covalent bond assembly. Meanwhile, the molecule displayed a strong CPL signal in the solid film, and the g lum values were gradually enlarged from −7.15 × 10−3 to −1.08 × 10−2 with the extension of the conjugation effect. This work illuminated the connection of chiral AIE liquid crystal molecules between conjugated structure and CPL property, providing a new strategy for constructing liquid crystal systems with efficient CPL properties. [Display omitted] • The CPL-active LC molecules ( R -BIN-OC and R -BIN-NC) based on BINOL-CS derivatives were prepared. • They demonstrated columnar phase LC and excellent AIE properties. • They showed a successful transfer of chirality from BINOL to the achiral CS. • The g lum value displayed ranged from −7.15 × 10−3 to −1.08 × 10−2 in solid film. [ABSTRACT FROM AUTHOR]

Two enantiomeric novel chiral stationary phases (CSPs) R-3-Amide-BINOL CSP (CSP-1) and S-3-Amide-BINOL CSP (CSP-2) were prepared using (R/S)-1,1'-bi-2-naphthol (BINOL) derivatives as chiral selectors. The structure of CSPs was characterized by nuclear magnetic resonance, scanning electron microscope and elemental analysis. Four chiral solutes were selected under normal phase HPLC conditions to evaluate the chiral separation ability of the two novel CSPs. The effects of mobile phase and acidic additives on enantiomeric separation were investigated. The combination of molecular docking simulation and experimental data has elucidated the crucial role of hydrogen bonds and π-π interactions formed between the analyte and CSP in chiral recognition, and different configurations of CSP can cause enantiomeric elution sequence reversal, indicating that the configuration of chiral selectors in CSP has a significant impact on chiral recognition ability., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Abstract A new probe, based on BINOL and ferrocene unit, senses Al3+ selectively among a variety of metal cations. Through different channels: anodic redox shift of the Fe(II)/Fe(III) redox couple, and a remarkable enhancement of the fluorescence. This fluorescence recognition of Al3+ also shows color changes under a UV lamp. Mass and NMR spectroscopic analyses have been used to study the mechanism, which indicates the formation of [1 + 2] complexes. Graphical abstract The new ferrocene derivative was synthesized and characterized, as very selective redox and fluorescent chemosensors for Al3+ cations, which exhibited fast response, high selectivity and sensitivity. Unlabelled Image Highlights • A new ferrocene derivative shows fluorescence response toward Al3+. • Coordination with 1 equiv. Al3+ leads to signal change in the redox potential of the ferrocene/ferrocinium redox couple. • The formation of the [1 + 2] complex was proposed. [ABSTRACT FROM AUTHOR]

A series of new chiral-bridged N-heterocyclic carbene ligands with different substituents and their corresponding palladium complexes have been synthesised. The effect of the substituents on the catalytic activity of these Pd complexes was investigated in the Suzuki reaction of p-bromotoluene with phenylboronic acid, and the results showed that the complexes with aryl substituents performed better than those with alkyl substituents. The complex with the most sterically hindered substituent (diisopropyl on a phenyl group) performed best, and it was also an efficient catalyst for the reaction of various arylboronic acids with aryl halides having different electronic and steric properties. In addition, it was employed as a catalyst in the asymmetric Suzuki reaction, but only moderate yields of 1,1-binaphthalenes with less than 20% enantiomeric excess were obtained. [ABSTRACT FROM AUTHOR]

An operationally simple ring closure of racemic 1,1′-bi-2-naphthol (BINOL) yielded the heterocyclic aromatic compound 7 H -dibenzo[ c , g ]carbazole (DBC). This one-pot method gave a good conversion and is suitable for gram-scale synthesis. DBC derivatives have high thermal durability, amorphous and crystalline structures with unique morphological properties, and semi-conducting behavior with potential applications in organic electronics. [ABSTRACT FROM AUTHOR]

A novel hole-transporting material ( Q221 ) is synthesized by introducing benzyl groups onto the 1,1′-bi-2-naphthol central core as edge chains and bis(4-methoxyphenyl)amine-substituted 9H-carbazole as donor groups. A reference molecule ( Q222 ) is prepared with hexyl edge chains. The introduction of edge chains influences their molecular orbital energy levels. Q221 -based CH 3 NH 3 PbI 3 perovskite solar cells with carbon counter electrode exhibit the highest power conversion efficiency of 10.37% at a low doping level of Li-TFSI/TBP (15 mM/100 mM), and that of Q222 -based cells is 8.87%. Q221 -based cells doping with Li-TFSI/TBP of 15 mM/100 mM shows much better photovoltaic parameters compared to those doping with Li-TFSI/TBP of 30 mM/200 mM, when aged in ambient air of 30% RH without encapsulation. The new binaphthol based hole-transporting materials shows a great potential in fabricating effective perovskite solar cells. [ABSTRACT FROM AUTHOR]

We have studied the intra- and inter-molecular chirogenesis events on a family of chiral bisporphyrin hosts H1-H3 . The three pairs of enantiomers for H1-H3 were constructed by connecting two zinc(II) porphyrinates to a homochiral ( R )-(+)- or ( S )-(−)-1,1′-bi-2-naphthol (BINOL) with ester or ether linkages. Split Cotton effects were observed for all of the bisporphyrin hosts. For each enantiomer, the sign of the bisignate CD couplets directly correlates to the stereostructure of the BINOL linker, namely a ( R )-BINOL linker leads to a negative CD couplet and vise versa . The CD intensities of the hosts are decreasing from H1 to H3 along with the increasing of the length and flexibility of the chemical linkages between BINOL and porphyrin subunits. The predictable CD signs and regularly changed CD intensities demonstrate the defined intramolecular asymmetric information transfer, by which the chirality of a BINOL linker is translated to a preferred chiral twist in the inter-porphyrin arrangement with tunable efficiency. Furthermore, the intermolecular binding of 4,4′-BiPyridyl (BiPy), as a typical achiral ditopic guest, to the series of hosts were detected by UV–Vis, 1 H NMR and CD spectroscopic titrations. The results indicate a convergent and complementary 1:1 binding mode, in which a BiPy ligand binds to a host molecule by ditopic Zn N coordination forming a stable cyclic supramolecular complex. In particular, the intensity of CD signals decreases significantly for all of the supramolecular complexes in comparison with the chiral bisporphyrin hosts alone, though the CD sign does not change. The observation is rationalized by DFT molecular modeling, which suggests that upon the formation of 1:1 cyclic supramolecular complexes the chiral twist direction of the two porphyrin moieties does not change, while the Zn Zn distance increases remarkably. The present results highlight the effects of intramolecular chirality induction and intermolecular chirality modulation in BINOL bridged porphyrin tweezer systems. [ABSTRACT FROM AUTHOR]

The H8BINOL-based perfluoroalkyl ketone ( S)- 2 is found to exhibit highly enantioselective fluorescent enhancements toward both unfunctionalized and functionalized chiral amines. It greatly expands the substrate scope of the corresponding BINOL-based sensor. A dramatic solvent effect was observed for the reaction of the amines with compound ( S)- 2. In DMF, cleavage of the perfluoroalkyl group of compound ( S)- 2 to form amides was observed but not in other solvents, such as methylene chloride, chloroform, THF, hexane, and perfluorohexane. Thus, the addition of another solvent, such as THF, can effectively quench the reaction of compound ( S)- 2 with amines in DMF to allow stable fluorescent measurement. This is the first example that the formation of strong amide bonds under very mild conditions is used for the enantioselective recognition of chiral amines. The mechanism of the reaction of compound ( S)- 2 with chiral amines is investigated by using various analytical methods including mass spectrometry as well as NMR and UV/Vis absorption spectroscopy. [ABSTRACT FROM AUTHOR]

Enantioseparation of 1,1′-bi-2-naphthol (BINOL) was performed on an immobilized polysaccharide-based chiral stationary phase (CSP), Chiralpak IA, in the normal-phase mode. The effects of polar modifier in the mobile phase and column temperature on retention, enantioseparation, and elution order were investigated. An interesting reversal of elution order for BINOL was observed. When ethanol was used as a polar modifier, R-BINOL was eluted first with marginal enantioseparation. Excellent enantioseparation was obtained when ethanol was replaced by 1-propanol, and S-BINOL was eluted first, this effect being retained with 2-butanol, 1-butanol, 1-pentanol or 1-hexanol as the modifier. When isoamyl alcohol was used, reversal of elution order was again observed, i.e., R-BINOL eluted first with marginal enantioseparation, similar to the case of ethanol. When cyclohexanol and cyclopentanol were used, R-BINOL was still eluted first, but enantioseparation was as good as with 1-propanol as the modifier. This is the first report of large enantioseparation obtained in both elution orders for a given selector/selectant system. A retention model based on stoichiometric displacement theory for retention (SDT-R) was investigated to fit the chromatographic data. The reason for solvent-induced reversal of elution order was elucidated based on a derivation of the retention model. Reversal of elution order for BINOL induced by the content of isoamyl alcohol was also predicted based on the model and confirmed by experiment. [ABSTRACT FROM AUTHOR]

Abstract: Charge-transfer complexes composed of 1,1′-bi-2-naphthol as an electron donor and viologen derivatives as electron acceptors exhibit thermochromic properties in the solid state without dramatical isomerization of the component molecules such as proton transfer. [ABSTRACT FROM AUTHOR]

Abstract: Enantioseparation of 1,1′-bi-2-naphthol (BINOL) was performed on a polysaccharide-based chiral stationary phase, Chiralcel OD-H, under normal-phase mode. The effects of polar modifier in the mobile phase on the retention, enantioseparation and elution order were investigated in detail. Solvent-induced reversal of elution order for BINOL was observed. When linear alcohols were adopted, R-BINOL was always eluted first. S-BINOL was eluted first when 2-propanol was used as a polar modifier. Enantioseparation could not be obtained when sec-butyl alcohol or tert-butyl alcohol was used as a polar modifier. When isoamyl alcohol or cyclohexanol was used as a polar modifier, favorable enantioseparation was obtained as with 1-pentanol or 1-hexanol; also, R-BINOL was the first-eluted enantiomer. It is worth emphasizing that significantly better enantioseparation was obtained when higher alcohols were used as polar modifier of the mobile phase. A nonlinear characteristic for the ln α against 1/T plots was universally observed in this study though the ln k against 1/T plots exhibited a linear feature. Associated with the obtained thermodynamic parameters, some interesting inferences about chiral recognition mechanism were proposed. [Copyright &y& Elsevier]

Abstract: A novel charge-transfer (CT) host system with a 1D column-like structure is developed. This 1D column-like structure is formed by the CT interactions between rac-6,6′-dibromo-1,1′-bi-2-naphthol (rac-1) and 1,1′-dimethyl-4,4′-bipyridinium dichloride (MVCl2). n-Alkyl alcohol molecules (guest molecules) can be introduced into the CT host system by tuning of the packing of its 1D CT column-like structure. The diffuse reflectance spectra (DRS) of this host system are sensitive to the type of guest molecules. [Copyright &y& Elsevier]

Abstract: A novel charge-transfer (CT) host system is developed using CT complexes composed of rac-3,3′-dihydroxy-1,1′-bi-2-naphthol and 1,1′-dibenzyl-4,4′-bipyridinium dichloride. This CT host complex has a 1D channel-like cavity in which guest (MeOH and EtOH) molecules can be discharged and adsorbed. The color and DRS of the CT crystals change according to the presence of guest molecules in the host complex. [Copyright &y& Elsevier]

Abstract: A charge-transfer (CT) complex, composed of rac-3,3′-dibromo-1,1′-bi-2-naphthol as the electron donor and 1,1′-dimethyl-4,4′-bipyridinium dichloride as the electron acceptor, is formed only by the inclusion of specific guest molecules. The color of this inclusion CT complex is sensitive to the component guest molecules. [Copyright &y& Elsevier]

The aim of this study was to observe the chiral separation of a series of C2-asymmetric bi-naphthyl compounds on molecularly imprinted polymers (MIPs) using 1,1′-bi-2-naphthol (BINOL) as template. MIP prepared using 4-vinylpyridine as the functional monomer showed better chiral recognition for the template than the MIPs prepared using acrylamide, 2-(diethylamino)ethylmethacrylate and 2-vinylpyridine, respectively. 1H-NMR was used for comparison of the interactions between template and functional monomers. For chromatographic analysis the effects of mobile phase and temperature on the chiral separation were investigated. When 4-vinylpyridine was employed as the functional monomer, chiral separation of 1,1′-bi-2-naphthol and its analogues were studied. The MIP also demonstrated an ability to discriminate between enantiomers of structurally related compounds that had not been imprinted. The thermodynamic parameters of interactions between substrates and MIP in acetonitrile based mobile phase were investigated by the Van’t Hoff equation. In this study, the specific hydrogen-bonding interactions seemed to be the key factor to achieve chiral separation. [ABSTRACT FROM AUTHOR]

Abstract: By using three types of viologen derivatives, we synthesized chiral charge-transfer (CT) complexes with an axially chiral 1,1′-bi-2-naphthol molecule and successfully controlled the crystal structure and inclusion ability of the third component by changing the viologens. [Copyright &y& Elsevier]

Abstract: Several new stationary phases were prepared to study the structure–activity relationship of the chiral resolution of racemic 1,1′-bi-2-naphthol with a modified dipeptide Asn-Asn selector. The number of amino acid, the side chain protecting groups of the amino acid, and the Fmoc end-capping group all proved important for enantioselectivity. The linker also influenced enantioselectivity. Influence of the length of the linker appears to be related to the accessibility of chiral selectors. The bond through which the selector is attached to the linker proved important. Based on these results, it is postulated that hydrogen bonding interactions between one side chain amide group of one Asn and the oxygen on the backbone of another Asn with the two hydroxyl groups of the analyte play an important role in the resolution of racemic 1,1′-bi-2-naphthol with the modified dipeptide Asn-Asn selector. [Copyright &y& Elsevier]

Abstract: N,N,N′,N′-Tetra-n-butyl-BINOL-3,3′-dicarboxamide 5d was found to promote phenyl transfer from ethylphenylzinc to both aromatic and aliphatic aldehydes with high enantioselectivity up to 96% ee in tert-butyl methyl ether. [Copyright &y& Elsevier]

Abstract: Crown ether-type macrocycles consisting of an enantiopure biarenol derivative and an oligoethylene glycol were synthesized by the Lewis acid-mediated tandem Claisen rearrangement. This is the first example of the successful application of the tandem Claisen rearrangement to the synthesis of enantiopure macrocyclic biarenol derivatives. The enantiopure macrocyclic biarenols were found to form 1:1 complexes with amino acid salts and to discriminate their chirality. [Copyright &y& Elsevier]

Abstract: The liquid-phase oxidative coupling reaction of 2-naphthol was carried out in dichloromethane solvent over vanadium catalysts supported on inorganic oxides such as MCM-41 using molecular oxygen as the oxidant. The main product was 1,1′-bi-2-naphthol, the oxidative Cg product of 2-naphthol. The yield of 1,1′-bi-2-naphthol increased with the increasing amount of supported V, but leveled off when the amount of V was more than about 1wt.%. The sterically bulky 1,1′-bi-2-naphthol was suggested to be mainly produced in the mesopores of the MCM-41 support in comparison with the activity of the V catalyst supported on NaZSM-5 support which has only micropores. The active vanadium species for the oxidative coupling product was found to be the tetrahedral V5+ species based on the correlation between the yield of 1,1′-bi-2-naphthol and the intensity of the tetrahedral V5+ species estimated by the DR spectra of the V/MCM-41 catalysts. [Copyright &y& Elsevier]

Pirkle-type chiral stationary phases (CSPs) based on (5)-leucine and (S)-phenylglycine were applied in the resolution of l,1'-bi-2-naphlhol and 3,3'- diaryl-l'-bi-2-naphthols. Among the two Pirkle-type CSPs. the one based on (S)-N- (3.5-dinitrobenzoyl)leucine N-propylamide was found to be excellent and most widely applicable. Interestingly, the elution orders for the resolution of l.1'-bi-2- naphthol on the CSPs based on (S)-N-(3,5-dinilrobenzoyl)eucine N-propylamide and (S)-N-(3,5-dinitrobenzoyl)phenylglycine N-propylamide were opposite to those for the resolution of 3,3'-diaryl-l'-bi-2-naphthols. In order to rationalize the reversed elution orders, we proposed two different chiral recognition mechanisms based on the chromatographie resolution behaviors, with the aid of the CPK molecular model study. [ABSTRACT FROM AUTHOR]

Abstract: Efficient resolution of racemic 1,1′-bi-2-naphthol, a well-studied analyte in chiral separation, was achieved using selectors developed from a small library. Separation factors (up to 7.2) obtained are significantly higher than the ones reported previously for this analyte. The library consists of 121 members and it does not contain the pi deficient 3,5-dinitrobenzoyl (Dnb) group. These highly efficient stationary phases may lead to the practical large-scale chromatographic resolution of enantiomers of 1,1′-bi-2-naphthol, which are widely used as chiral auxiliaries and ligands in asymmetric synthesis. [Copyright &y& Elsevier]

The chiral recognition ability of single and dual selectors, that were used as additives, have been investigated by HPLC and CE. Native β- and γ-cyclodextrins, permethylated β-cyclodextrin, hydroxypropyl-β-cyclodextrin, cholic acid and taurodeoxycholic acid sodium salts were applied as chiral selectors, whereas the atropisomers of 1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, and 1,1′-bi-2-naphthol served as model compounds. It was found that all investigated selectors, except for γ-cyclodextrin, display the same affinity pattern for binaphthyl enantiomers, i.e., binding the S more strongly than the R enantiomer. However, the differences in the phase distribution of chiral selectors led to the opposite elution order of enantiomers: with cyclodextrins, the first eluted is S enantiomer, while R is the first eluted for bile salts. Under the conditions studied, cyclodextrins (except γ-cyclodextrin), as well as cholic acid sodium salts acting singly, enable the separation of 1,1′-binaphthyl-2,2′-diyl hydrogenphosphate enantiomers both by HPLC and CE methods, while 1,1′-bi-2-naphthol enantiomers were resolved only under CE conditions with permethylated cyclodextrin or bile salts. In both techniques the application of dual systems could improve resolution or make it worse (or even cancel), depending on the sign of enantioselectivity of particular selectors, their concentrations and localization: mobile or stationary phase. It has been found that the mechanism of separation as well as interactions occurring between two selectors may be followed by using combined HPLC and CE methods. The obtained results proved that, as well as β-CD, TM-β-CD and γ-CD also form inclusion complexes with cholic acid sodium salts. The reversal of elution order may be realized by two procedures: changing a single selector, i.e., cyclodextrin on cholic acid sodium salt or vice versa, and by changing the proportion of selectors in the combined bile salt–cyclodextrin system. [Copyright &y& Elsevier]

Aimed at investigating the monolayers and Langmuir–Blodgett (LB) films of compounds without any substituted alkyl chains and constructing chiral ultrathin films, a new group of optically active macrocyclic poly(ether sulfone)s containing a binaphthyl group, which have no substituted alkyl chains, were synthesized. The spreading behavior and the ultrathin film fabrication of these compounds was studied. Stable monolayers with collapse surface pressures up to 40 mN m−1 were formed at the air/water interface and uniform LB films were fabricated by using the horizontal lifting method. The optical activities of the compounds were maintained in the LB films. Transferred LB films were characterized by UV-vis, fluorescence and circular dichroism spectroscopy. It was found that the 1Bb, 1La and 1Lb bands of the compounds showed a red shift compared with the corresponding solutions. While no split of the Cotton effect was observed for the dimeric compound, strong exciton couplings that could be ascribed to the interactions between the naphthyl groups were observed for the trimeric macrocyclic compounds. [Copyright &y& Elsevier]

Inclusion reaction of racemic 1,1′-bi-2-naphthol and ( S)-proline was examined under the solid state and the solid-liquid conditions. The results indicated that a solid mixture of racemic 1,1′-bi-2-naphthol and ( S)-proline in a 1∶1 molar ratio was kept at 50–80 °C for 3–4 h, followed by treatment with benzene to give an insoluble solid and a benzene solution, from which ( S)-(−)- and ( R)-(+)-1,1′-bi-2-naphthols of a modest level of optical purity were obtained. After “kinetic” crystallization, both essentially enantiopure isomers were provided in 15%–35% overall yields, respectively. [ABSTRACT FROM AUTHOR]

The enantioselective Michael addition of 2-alkoxyphenyl esters of α-substituted β-keto acids to non-prochiral α,β-unsaturated carbonyl compounds catalyzed by 5–10 mol % of sodium 2′-[2-(2-methoxyethoxy)ethoxy]-1,1′-binaphthalen-2-oxide afforded the desired adducts in high yields with up to 97% ee. [ABSTRACT FROM AUTHOR]

An improved method for preparing enantiomerically pure 1,1′-bi-2-naphthols is described. 1,1′-bi-2-naphthol boric anhydride was generated from the reaction of racemic 1,1′-bi-2-naphthol and boric anhydride. Its two diastereoisomers, could be efficiently separated in THF using (L)-proline as the resolving agent. Treatment in three successive steps yielded 79% and 74% enantiomerically pure (S)-and (R)-1,1′-bi-2-naphthol respectively. [ABSTRACT FROM AUTHOR]