Benzonitrile Research Articles

Removal of benzonitrile and carbazole from model green-diesel derived from microalgae using metal-organic frameworks with protonated amines

The utilization of microalgae-derived fuel is very important for our sustainability. Here, adsorptive denitrogenation of model green-diesel (with considerable nitrogen-containing compounds, NCCs) was investigated to check the feasibility of adsorptive purification of fuel, derived from microalgae that is composed of NCCs. A highly porous MIL-101(Cr) (named M101) metal–organic framework was firstly modified to introduce protonated amino groups on both the linker and metallic sites of the MOF. The functionalized MOFs including P-M101-NH2-ED (P and ED mean ‘protonated’ and ethylenediamine, respectively), M101-NH2-ED, and M101-NH2 were applied (together with pristine M101 and a conventional activated carbon) in the adsorptive removal of N-containing compounds like benzonitrile (BENZ) and carbazole (CARB) from model green-diesel. The prepared P-M101-NH2-ED showed the most effective performances in the adsorption, compared with any other adsorbents known thus far. For instance, P-M101-NH2-ED adsorbed 15.6 and 3.6 times of BENZ and CARB, respectively, that of the activated carbon. The observed remarkable performances of P-M101-NH2-ED (Q0 values for BENZ and CARB are 500 and 455 mg/g, respectively), although with lower porosity than other M101s, for BENZ and CARB adsorption could be explained mainly with hydrogen bonding and hydrogen bonding/cation-π interactions, respectively. Moreover, P-M101-NH2-ED was recyclable in several cycles after simple ethanol washing. Therefore, P-M101-NH2-ED could be suggested as a plausible adsorbent to remove NCCs from green-diesel, based on remarkable performances and facile reusability.

Ph–Cn as a Novel Ecl Emitter Combining Catalysis and Luminescence in One

Ph–Cn as a Novel Ecl Emitter Combining Catalysis and Luminescence in One

Reactivity studies and structural outcomes of a bulky dialkylaluminium amide in the presence of the N-heterocyclic carbene, ItBu

Aluminium reagent iBu2Al(TMP) (TMP is 2,2,6,6-tetramethylpiperidide) has previously shown interesting synergistic metallation chemistry when paired with alkali metal amides. Here its structural chemistry and reactivity is explored in the presence of the N-heterocyclic carbene, ItBu, 1,3-di-tert-butylimidazol-2-ylidene. Abnormal aItBu structures are obtained with iBu2Al(TMP) on its own and in the co-presence of LiTMP, NaTMP or KTMP. Reaction with phenol is stoichiometric dependent leading to the diphenolate [ItBu(H)]+ [(PhO)2Al(iBu)2]− and triphenolate [ItBu(H)]+ [(PhO)3Al(iBu)]− ionic complexes. Dinuclear aItBu(Ph)CN[Al(iBu)2NC(TMP)Ph]Al(iBu)2 was the surprising product from reaction with benzonitrile, displaying an imidoC- and (iBu)2Al- disubstituted imidazolium ring as well as a second imido unit made by addition of “non-nucleophilic” TMP across the benzonitrile triple bond. Potential insight into the mechanism of this intriguing complicated reaction was gained through the crystallographic characterisation of the ketamide [iBu2AlNC(Ph)TMP]2, a possible intermediate. Reaction with Ph2CHCN, diphenylacetonitrile, proved more straightforward affording the ionic complex [ItBu(H)]+ [Ph2CCN]−.

Oxidative modification of metal-organic framework-derived carbon: An effective strategy for adsorptive elimination of carbazole and benzonitrile

The elimination of nitrogen-containing compounds (NCCs), such as carbazole (CARB) and benzonitrile (BENZ), from fuels is essential before use. In this study, an efficient adsorbent was prepared through oxidative modification of metal-organic framework (MOF)-derived carbon to effectively remove NCCs from fuel. The prepared adsorbent, oxidized MOF-derived carbon (OMDC), showed noticeable performance in removing NCCs from model fuel. OMDC showed 4- and 26-times the adsorption capacity for the removal of CARB and BENZ, respectively, compared with that of activated carbon. Moreover, OMDC showed the highest adsorption capacity for CARB and BENZ removal compared with any adsorbent reported thus far. The adsorption process could be explained by hydrogen bonding based on the presence of many hydrogen donor and acceptor sites on the developed adsorbent. Furthermore, the adsorbent could be reused several times for NCCs adsorption after simple ethanol washing. Therefore, OMDC is a potential adsorbent for the elimination of NCCs from fuels.

Selective hydrogenation of benzonitrile and its homologues to primary amines over platinum

Various supported precious metal (Pt, Rh, Ru, Ir) catalysts have been screened in the reduction of benzonitrile (BN), benzyl cyanide (BC) and 3-phenylpropionitrile (PPN) to benzylamine (BA), 2-phenylethylamine (PEA) and 3-phenylpropylamine (PPA), using our method for selective, heterogeneous, palladium-catalysed hydrogenation of nitriles to primary amines developed previously. A readily available platinum on carbon catalyst (10% Pt/C) afforded the best results obtaining complete conversion of nitriles, as well as comparatively high isolated yields (58–70%) and selectivities to primary amines (57–68%) under mild and optimized conditions [6 bar, 30 °C, two immiscible solvents (dichloromethane/water or toluene/water), acidic additives (NaH2PO4, (NH4)H2PO4 or H2SO4)]. Contrary to the typical high secondary amine selectivity of platinum, surprisingly, this Pt/C catalyst proved to be much more effective and selective in the formation of PEA and PPA than a Pd/C one applied earlier. To clear the divergences in the primary amine selectivity observed, quantum chemical calculations (DFT) were accomplished related to the adsorption interactions between the imine intermediates and platinum.

Influence of dielectric, Electro-Optic Kerr Effect and spectroscopic characterisation on polar–polar binary liquid mixture

ABSTRACT Complex dielectric spectra of the binary mixture of benzonitrile (BNZ) with acetophenone (ACPH) have been carried out at 11 different concentrations in the frequency range of 10 MHz to 40 GHz at four different temperatures (10°C, 15°C, 20°C and 25°C) using Time Domain Reflectometry technique. Static dielectric constant (ε0), relaxation time (τ) are obtained for above mentioned temperatures using nonlinear least squares fit method and density and refractive index are obtained at room temperature (25°C). These parameters are used to calculate the excess static dielectric constant (ε0 E) and excess inverse relaxation time (1/τ)E, excess molar volume (Vm E), effective Kirkwood correlation factor (geff), Bruggeman factor (fB) and thermodynamic parameters such as enthalpy and entropy of activation of BNZ-ACPH mixture. Static dielectric constant decreases with increasing temperature and increasing concentration of ACPH in BNZ. The deviance in the excess parameters shows the strength of the molecular interactions and the presence of intermolecular interaction between unlike molecules. The measurement of Kerr constant (B) of the binary mixture of BNZ-ACPH have been reported for the wavelengths 632.8 nm and 512 nm for 5 different concentrations at room temperature using Electro-Optic Kerr Effect method. The change in the Kerr constant was observed for the different concentrations associated with the pure liquids. This deviation shows the non-additive behaviour and which is in good agreement with the dielectric parameters of the system under study. Also, the FTIR spectra have been obtained of BNZ-ACPH mixture to have a good agreement with the dielectric study.

Designing of small molecule non-fullerene acceptors with cyanobenzene core for photovoltaic application

A quantum chemical analysis of four star-shaped anisotropic acceptor molecules (A1-A4) having acceptor-acceptor′-acceptor (A-A′-A) architecture has been performed for solar cell applications. The designed acceptors consist of cyano benzene as central core, thiophene as π-bridge and 2-methylenemalononitrile (A1), 6-methylene-2-thioxo-1,3-thiazinan-4-one (A2), 2-(2-methylene-3-oxo-2,3-dihydro-1H-inden-1ylidene) malononitrile (A3) and 5-methylene-2-thioxothiazolidin-4-one (A4) as peripheral acceptor units. DFT and TD-DFT calculations were performed using selected MPW1PW91 to assess optical, electronic and charge transfer properties of acceptors (A1-A4) which were further characterized through frontier molecular orbitals (FMOs), DOS, reorganization energies, TDM and open-circuit voltage analysis. The results dictated that the substitution of different acceptor units on the three sides of cyano benzene core forming star-shaped molecules can fine tune the FMO energies, absorption properties (between 470 and 524 nm), band gap energies and reorganization energies in accordance with R. Among all acceptors, A3 exhibited exclusively high absorption value (524 nm), lowest band gap (2.46 eV) and lowest hole reorganization energy (0.0037 eV). Moreover, the acceptor molecules have comparable values of open-circuit voltage to R making them quite suitable for photovoltaic applications in OSCs. The electron-deficient core-based acceptors, in this study, open a new door for designing high-performance OSC acceptors.

Alkaline Earth Metal Imido Complexes with Doubly Deprotonated Amidine and β‐Diketimine Ligands

Double deprotonation of the amidine DIPP‐N=C(tBu)‐NH2 or β‐diketimine DIPP‐N=C(Me)‐C(H)=C(Me)‐NH2 (DIPP = 2,6‐diisopropylphenyl) with strong benzylcalcium or strontium bases gave metal imido complexes with the anions DIPP‐N=C(tBu)‐N2– (Am2–) and DIPP‐N=C(Me)‐C(H)=C(Me)‐N2– (BDI2–) which crystallized as tetrameric complexes with typical Ca4N4 or Sr4N4 cubane frameworks. Crystal structures of [(Am)Ca·THF]4, [(BDI)Ca·THF]4 and the first Sr imido complex [(Am)Sr·THF]4 are presented. Calculated geometries of [(Am)Ca·THF]4 and [(BDI)Ca·THF]4 (B3PW91/6‐311++G**) are in good agreement with the crystal structures. Also complexes with monoanionic ligands (Am‐H)– and (BDI‐H)– are reported. Charge delocalization in the ligand backbone is discussed. Ligand–metal bonds are calculated to be circa 90 % ionic; the NPA charges on Ca is circa +1.8. The negative charge on the ligand is delocalized over the ligand backbone but there is still considerable electron density on the terminal N (–1.4). Despite this high negative charge, the reactivity of these complexes is generally low due to the strongly bound cubane core. Reaction of [(Am)Ca·THF]4 with phenyl cyanide gave the [(Am)Ca·PhCN]4, clearly demonstrating its low reactivity. Attempts to break the tetrameric cluster in smaller aggregates by addition of 18‐crown‐6 led to protonation and isolation of (Am‐H)2Ca·(18‐crown‐6). Reaction of [(Am)Ca·THF]4 with iPrN=C=NiPr gave after addition a complex with a unique amido‐guanidinate ligand.

Thermodynamic and spectroscopic studies of intermolecular interactions between isoamyl alcohol and monocyclic aromatic non-ideal binary liquid mixtures

The thermodynamic properties such as excess volume ( V E ), excess Gibbs free energy ( G* E ), deviation in viscosity ( Δη ) and deviation in isentropic compressibility ( Δκ s ) have been calculated using the experimental data of density ( ρ ), viscosity ( η ) and speeds of sound ( u ) values of binary mixtures namely; isoamyl alcohol (IAA) + chlorobenzene (CB), + benzonitrile (BN), + aniline (AL), + benzaldehyde (BZ) and + nitrobenzene (NB) over the entire range of mole fraction at temperature 298.15, 303.15 and 308.15 K and under atmospheric pressure. The obtained results were fitted to the Redlich-Kister (R-K) equation to determine the adjacent binary coefficients with errors. The calculated parameters were discussed in terms of intermolecular interactions such as H-bonding, OH- π , and molecules fitting interactions in the non-ideal solutions. Further, the pure liquids and their mixture concentrations were characterized by FT-IR, and 1 H-NMR spectral technologies and using these spectral results elucidate intermolecular interaction (H-bond) in dissimilar molecules.

Multimetal Incorporation into 2D Conductive Metal-Organic Framework Nanowires Enabling Excellent Electrocatalytic Oxidation of Benzylamine to Benzonitrile.

As an important organic intermediate, benzonitrile (BN) is widely involved in organic synthetic chemistry and pharmaceutical and dyestuff industries. However, the exploration of a more efficient and controllable synthesis technique and the corresponding greener catalysts for the synthesis of BN still poses a great challenge. Herein, with multimetallic two-dimensional conductive metal-organic frameworks (2D cMOF) as anodic electrocatalysts, we develop a green, convenient, and highly efficient electrochemical synthesis strategy for BN. Thanks to the intrinsic 2D electrically conductive structure and the optimized the multimetallic coupling catalytic effect, the resulting multimetallic 2D cMOFs exhibit excellent benzylamine (BA) electrooxidation performance. Especially, the trimetallic 2D cMOF (NiCoFe-CAT) requires an ultralow potential of 1.29 V vs reversible hydrogen electrode (RHE) to achieve a 10 mA·cm-2 current density, which indicates the fastest reaction and the most favorable thermodynamic condition. A very high yield (0.058 mmol·mg-1·h-1) and faradic efficiency (∼87%) of benzonitrile are both achieved during the BA electrooxidation reaction at 1.45 V. The reaction mechanism investigations indicated that the various redox mediators of MII/MIII (Ni, Co, Fe) may be regarded as multimetal active species to promote BA conversion. Also, the excellent cycling durability of multimetallic 2D cMOFs further promotes their potential practical applications. These electrocatalytic performances are considered excellent and nearly surpass all other reported Ni-based inorganics or MOF-based electrocatalysts for the electrocatalytic oxidation of benzylamine.

Oyster shell-based alkalinization and photocatalytic removal of cyanide as low-cost stabilization approaches for enhanced biogas production from cassava starch wastewater

Cassava starch wastewater (CSW) poses a high polluting potential due to its high organic loading and cyanide (CN−) concentration, but this residue can be pretreated and reused. The present work proposes stabilizing the CSW pH and degrading CN- to optimize biogas production. To control the acidity of the CSW we used natural oyster shells as source of CaCO3, and the photocatalytic degradation of CN− was achieved with Degussa P25 TiO2. Natural oyster shells raised pH from 4.5 to 6.2 over 6 h of reaction, efficiently controlling the effluent acidity. After pH stabilization, the TiO2 photocatalyst tested in a degradation process under visible light was able to reduce CN− concentration by 73.02 %. After these pretreatments (pH stabilization and CN- degradation), the CSW was inoculated with sewage sludge (SS) to produce biogas. The pretreatments were proved to be efficient at favoring biogas production as this was heightened by 27.6 %. In addition, the pretreated CSW and digestate (anaerobic digestion) significantly reduced the toxicity of the effluent, assessed by investigating lettuce seeds (L. sativa) germination and root growth. Thus, pretreatments and reuse of residues may potentially provide socio-environmental and economic benefits.

Heterogeneous Catalytic Hydrogenation of 3-Phenylpropionitrile over Palladium on Carbon.

A previously developed and industrially feasible process for selective, Pd-mediated, liquid-phase heterogeneous catalytic hydrogenation of nitriles to primary amines was extended to the reduction of 3-phenylpropionitrile (PPN) to 3-phenylpropylamine (PPA). PPN, which belongs to the homologous series of benzonitrile (BN) and benzyl cyanide (BC), was hydrogenated under mild reaction conditions (30–80 °C, 6 bar), over Pd/C, in two immiscible solvents (dichloromethane/water) and using acidic additives (NaH2PO4 and H2SO4). Although relatively high conversion (76%) was achieved, the selectivity to PPA (26%) and its isolated yield (20%) were lesser than those in the case of the hydrogenation of BN or BC reported earlier. However, the purity of PPA was >99% without using any purification method. Quantum chemical calculations using a density functional theory (DFT) method were performed to compare the adsorption interactions of the different imine intermediates on palladium, as well as to clarify the differences observed in the primary amine selectivity. PPA is a valuable intermediate for the synthesis of carboxypeptidase B enzyme inhibitors, antimuscarinic drugs, or potential anticancer agents in the pharmaceutical industry.

Physicochemical studies of intermolecular interactions in 1-butyl-3-methylimidazolium tetrafluoroborate + benzonitrile binary mixtures at temperatures from 293.15 to 318.15 K

ABSTRACT The densities, ρ, speeds of sound, u, viscosity, η and refractive indices, n D of 1-butyl-3-methylimidazolium tetrafluoroborate [Bmim][BF4] and Benzonitrile (BN) binary mixture, including those of pure liquids have been measured over the entire composition range at temperatures (293.15, 298.15, 303.15, 308.15, 313.15 and 318.15 K) and at atmospheric pressure. From the experimental values, excess molar volumes, , excess isentropic compressibilities, , excess speeds of sound, , excess molar isentropic compressibilities, and deviations in viscosity, Δη, deviations in refractive index, and deviations in molar refraction, were calculated. The partial molar volumes and partial molar isentropic compressibilities along with their excess values over whole composition range and those of the components at infinite dilution were also calculated. The resultant positive or negative deviations of these parameters have been analysed in terms of molecular interactions prevailing in these mixtures. The applicability of Prigogine–Flory–Patterson (PFP) theory in predicting the values is checked.

Achieving Efficient Blue Delayed Electrofluorescence by Shielding Acceptors with Carbazole Units.

The design and synthesis of blue thermally activated delayed fluorescence (TADF) emitters that have high electroluminescence efficiency and low efficiency roll-off features remain a great challenge. Herein, we developed a facile and efficient strategy by shielding acceptors with carbazole units for constructing high-performance blue TADF emitters. Benzonitrile (BN), 9,9-diphenylacridan (DPAc), and carbazole (Cz) were adopted as the acceptor, donor, and protector, respectively, to build two TADF emitters named DPAc-DCzBN and DPAc-DtCzBN. The nondoped organic light-emitting diodes (OLEDs) of DPAc-DCzBN as the emitter exhibited a standard sky-blue emission with Commission Internationale de L'Eclairage (CIE) coordinates of (0.16, 0.26), high external quantum efficiency (EQE) of 20.0%, and low efficiency roll-off (EQEs of 19.5, 16.1, and 12.6% at 100, 500, and 1000 cd m-2, respectively), which is an outstanding nondoped blue TADF OLED. The doped device of DPAc-DtCzBN displayed a pure blue emission and the corresponding CIE coordinates are (0.16, 0.15). Meanwhile, it also demonstrated high and stabilized EQE values of 23.1, 18.3, and 11.5% at maxima, 100 and 500 cd m-2, respectively, which is a quite high level among the pure blue TADF OLEDs. This study testifies the feasibility of our strategy in constructing high-performance TADF electroluminescent materials.

Pd-containing Mono- and Bimetallic Nanoparticles Incorporated in Highly Porous Hypercrosslinked Polystyrene as Effective Catalysts of Suzuki Cross-coupling

This paper describes synthesis of Pd-containing catalysts of Suzuki cross-coupling based on non-functionalized hyper-crosslinked polystyrene (HPS) at variation of Pd precursor nature (PdCl2, PdCl2(CH3CN)2 or PdCl2(PhCN)2). Relatively low affinity of Pd species to the chosen polymeric support was shown to be responsible for in situ formation of Pd nanoparticles and their aggregates. During the investigation of aryl halide nature, catalytic activity was shown to decrease in the following order: Br > I > Cl. Best results were obtained for the preliminarily reduced HPS-based sample synthesized while using PdCl2 in the reaction between phenylboronic acid and 4-bromoanisole: more than 93% yield of cross-coupling product was achieved at mild reaction conditions (NaOH, 60oC, solvent ethanol-water mixture) using 0.8 mol.% of Pd.

CREATION, PHYSICAL AND CHEMICAL PROPERTIES OF ALKIL-2-((5-PHENETHYL-4-R-1,2,4- TRIAZOLE-3-YL)THIO)ACET(PROPAN,BENZ)IMIDATES

Objective: The aim of this research was to synthesize and evaluate physical-chemical properties of 5-pheneyhyl-4-R-3-thio-1,2,4-triazole and to establish identity and structure of the synthesized compounds, namely alkil-2-((5-phenethyl-4-R-1,2,4-triazole-3-yl)thio)acet(propan,benz)imidates.
 Methods: As starting materials for synthesis of alkil-2-((5-phenethyl-4-R-1,2,4-triazole-3-yl)thio)acet(propan,benz)imidates, the corresponding 2-((5-phenethyl-4-R-1,2,4-triazole-3-yl)thio)aceto(propane,benzo)nitrile have been used. Synthesis has been set in the absolute alcohol medium (propanol or butanol alcohol) with chloroform, using the saturation with dry hydrogen chloride.
 Results: In this study, we have developed nine new compounds have been received as a result of synthetic transformations, the structure of synthesized compounds has been confirmed by modern complex of physical-chemical methods of analysis (1H NMR-spectroscopy, elemental analysis), and their individuality has been conducted on gas-liquid chromatograph Agilent 1260 Infinity HPLC equipped with a mass spectrometer Agilent 6120.
 Conclusion: As a result of the work, it was synthesized the new compounds of the series of alkil-2-((5-phenethyl-4-R-1,2,4-triazole-3-yl)thio) acet(propan,benz)imidates and was characterized by elemental analysis and proton nuclear magnetic resonance spectroscopic analysis.

Nickel‐Catalyzed Hydrophosphonylation and Hydrogenation of Aromatic Nitriles Assisted by Lewis Acid

AbstractIn this paper, we describe the catalytic hydrophosphonylation of several aromatic nitriles used to synthesize α‐aminophosphonates (α‐APs) using commercially available trialkyl phosphites (P(OR)3, R=Et, iPr, Bu,) and simple and inexpensive nickel chloride (NiCl2.6H2O) as the catalytic precursor. The use of triethylborane (Et3B) as a Lewis acid (LA) was mandatory in order to successfully perform H‐phosphite moiety incorporation at the CN bond of non‐activated benzonitriles (BN) derivatives. Interestingly, when a highly activated BN such as 2,3,4,5,6‐pentafluorobenzonitrile (BN‐g) was employed, it was possible to perform the reaction in the absence of an LA using milder reaction conditions. Also, we found that using HP(O)(OiPr)2 as a starting material afforded the aminobisphosphonate derivative with better selectivity than using the method involving P(OiPr)3 as the initial reagent. Remarkably, when using HP(O)(OiPr)2 with an excess of Et3B, the reaction's selectivity completely changed to yield N‐benzyl‐ benzylimine (BBI) and 2,4,5‐triphenylimidazole.

The synthesis and physicochemical properties of alkyl-2-(3-thio-5-(1Н-tetrazole-1-yl)methyl-4-R-4Н-1,2,4-triazole-3-yl)ethan(propan,benz)imidates

The synthesis of new biologically active compounds that will replace expensive foreign medicines at the pharmaceutical market of Ukraine is one of the most important directions in development of modern pharmacy and medicine. The synthesis, study of physicochemical and biological properties of new compounds containing 1,2,4-triazole and 1 H -tetrazole cores are important tasks of modern synthetic chemistry. Aim. To synthesize new highly efficient and low-toxic substances, namely alkil-2-((5-(1 Н -tetrazole-1-yl)methyl-4-R-1,2,4-triazole-3-yl)thio)etan(propan,benz)imidates, and study physicochemical properties of all compounds synthesized. Results and discussion. Twelve new compounds have been obtained as a result of synthetic transformations, the structure of compounds synthesized has been confirmed by modern complex of physicochemical methods of analysis (IR-spectrophotometry, 1 H NMR-spectroscopy, elemental analysis), and their individuality has been proven on an Agilent 1260 Infinity HPLC high-performance liquid chromatograph equipped with an Agilent 6120 mass spectrometer. Experimental part. As starting materials for the synthesis of alkil-2-((5-(1 Н -tetrazole-1-yl)methyl-4-R-1,2,4-triazole-3-yl)thio)etan(propan,benz)imidates the corresponding 2-((5-(1 Н -tetrazole-1-yl)methyl-4-R-1,2,4-triazole-3-yl)thio)aceto(propane,benzo)nitriles were used. The synthesis was carried out in the absolute alcohol medium (propanol, butanol, octanol or allyl alcohol) with chloroform. Conclusions. During synthetic and physicochemical studies the preparative methods for the synthesis of alkil-2-((5-(1 Н -tetrazole-1-yl)methyl-4-R-1,2,4-triazole-3-yl)thio)etan(propan,benz)imidates have been developed, the structure of the compounds synthesized has been determined and finally confirmed.

Synthesis and Mesocrystalline Properties of Glassy Liquid Crystal Compounds Based on Tetrathiofuvalene and Cyanobenzene

Synthesis and Mesocrystalline Properties of Glassy Liquid Crystal Compounds Based on Tetrathiofuvalene and Cyanobenzene

Quantum Mechanical Study on the π-π Stacking Interaction and Change in Conformation of Phenolic Systems with Different Intermolecular Rotations

Aromatic systems like phenol, diphenol, cyano benzene, chloro benzene, aniline etc shows effective π-π stacking interactions, long range van der Waals forces; ion-π interactions etc. and these forces of interactions play an crucial role in the stability of stacked π-dimeric system. On the other hand, substituents and conformational change in the stacked dimmers of aromatic system may also change the stability of different stacked dimers. In this current study, stacked phenolic dimmers (both phenol and diphenol) have been taken for investigation of the stacking π-π interaction. But, the stacking interactions are also greatly affected by the conformational change with internal rotation (i.e. dihedral angle, φ) between the stacked dimers. It is generally accepted that larger basis sets are required for the highly accurate calculation of interaction energies for any stacked aromatic models. But, it has recently been reported that M062X/6-311++G(d,p) basis set is effectively better than that of B3LYP/6-311++G(d,p) for determining the interaction energies for any kind of long range interaction in aromatic systems. Therefore, all the calculations were carried out by using M062X/6-311++G(d,p) basis set. However, in most of the cases the calculated π-π stacking interaction energies show almost same result for both DFT and ab initio methods.