5341-44-6Relevant academic research and scientific papers
T3P-promoted synthesis of a series of novel 3-aryl-2-phenyl-2,3-dihydro-4H-1,3-benzothiazin-4-ones
Silverberg, Lee J.,Pacheco, Carlos,Sahu, Debashish,Scholl, Peter,Sobhi, Hany F.,Bachert, Joshua T.,Bandholz, Kaitlyn,Bendinsky, Ryan V.,Bradley, Heather G.,Colburn, Baylee K.,Coyle, David J.,Dahl, Jonathon R.,Felty, Megan,Fox, Ryan F.,Gonzalez, Kyanna M.,Islam, Jasra M.,Koperna, Stacy E.,Moyer, Quentin J.,Noble, Duncan J.,Ramirez, Melissa E.,Yang, Ziwei
, p. 1797 - 1805 (2020/02/05)
A series of 11 novel 3-aryl-2-phenyl-2,3-dihydro-4H-1,3-benzothiazin-4-ones was prepared at room temperature by T3P-mediated cyclization of N-aryl-C-phenyl imines with thiosalicylic acid. This provides simple and ready access to N-aryl compounds in this family, which have been generally difficult to prepare.
Facile route for green synthesis of N-benzylideneaniline over bimetallic reduced graphene oxide: chemical reactivity of 2,3,4-substituted derivatives of aniline
Aman, Razia,Sadiq, Saima,Ali, Muhammad,Sadiq, Muhammad,Gul, Jehan,Saeed, Khalid,Khan, Adnan Ali,Shah, Sagheer Hussain
, p. 2947 - 2961 (2019/02/28)
Mn–Co-decorated reduced graphene oxide (Mn–Co–rGO) was prepared by modified condensation method and characterized through XRD, SEM, EDX, FTIR and BET surface area analysis. The prepared sample was explored for its activity in the synthesis of N-benzylideneaniline (N-BA) using benzyl alcohol and PhNH2 as precursors. The catalyst has been used efficiently with high activity and selectivity for oxidation of benzyl alcohol to benzaldehyde in the presence of molecular oxygen, which further react with aniline to produced N-BA with sustainable catalytic activity up to five cycles. Furthermore, the effect of the nature and position of the substituent on aniline on the chemical reactivity of the nucleophile was studied theoretically using density functional calculations.
Oxidation of aromatic anils in aniline moiety by meta-chloroperbenzoic acid in aqueous acitic medium
Venkatesh,Karunakaran
, p. 2851 - 2855 (2015/12/12)
The kinetics of oxidation of aromatic anils in aniline moiety by meta-chloroperbenzoic acid (m-CPBA) has been studied in aqueous acitic medium. The order of reaction was found to be second order with respect to aromatic anil and first order with respect to m-chloroperbenzoic acid. The increase of [H+] in this oxidation retards the rate of reaction. The effects of substituents on the oxidation rate were studied with 3 meta- and 5 para-substituted anils at five different temperatures. Thermodynamic parameters for the oxidation have been determined and discussed. meta-Chloroperbenzoic acid oxidation with substituted anils fulfills the isokinetic relationship and Exner relationship but not to any of the linear free energy relationships. The deviation of Hammett plot was noted and a concave downward curve was obtained for the anils with substituents in aniline moiety.
Oxidation of aromatic anils by sodium perborate in aqueous acetic Acid Medium
Venkatesh,Karunakaran
, p. 739 - 744 (2014/06/09)
The kinetics of oxidation of 9 meta- and 15 para- substituted aromatic anils by sodium perborate were investigated in aqueous acetic acid medium. The reaction was second order with respect to aromatic anil and first order with respect to the sodium perborate. The increase of [H+] in this oxidation retards the rate of the reaction. The observed rate constant for the substituents were plotted against the Hammett constant, δ and a non-linear concave downward curve was obtained for the anils with substituents in the aniline moiety. The observed break in the log kobs versus δwas attributed to the transition state whereas the non-linear concave upward curve was observed for the substituents in the benzaldehyde moiety and a non-linear concave upward curve was observed for the substituents in the combination of aniline and benzaldehyde moiety. The electron withdrawing substituents fall on one side of the curve, having a negative ρvalue and the electron releasing substituents fall on the other side, with a positive ρvalue and a suitable mechanism was proposed.
Grinding synthesis of schiff bases combined with infrared irradiation
Tong, Jian-Ying,Sun, Na-Bo,Wu, Hong-Ke
, p. 5399 - 5401 (2013/07/26)
Solid-phase synthesis combined with infrared irradiation promoted the formation of a series of Schiff bases in the condensation reaction between substituted benzaldehydes and anilines, in the solvent free. Benzaldehydes and anilines, containing either electron withdrawing or electron-releasing groups, were evaluated their substituent effect on the formation of the Schiff bases. Moreover, this new procedure is environmentally benign because no solvent was employed in the transformations.
Kinetic investigation of oxidation of aromatic anils by potassium peroxymonosulfate in aqueous acidic medium
Venkatesh,Karunakaran
, p. 542 - 550 (2013/07/26)
The kinetics of oxidation of aromatic anils to benzaldehyde and azobenzene by potassium peroxymonosulfate has been studied in aqueous acetic acid medium. The low dielectric constant of the medium facilitates the reactivity. It has been found that the variation in the ionic strength of the reaction has a negligible effect on the rate. Similarly, polymerization was not observed when acrylonitrile was added to the reaction mixture. This observation rules out the formation of any free radical in the reaction. The added Mn(II) increases the rate of the reaction, which indicates the involvement of two-electron transfer. Highly negative ΔS# values indicate a structured transition state. The deviation of the Hammett plot was noted, and a concave downward curve was obtained for the anils with substituents in the aniline moiety. The observed break in the log kobs versus σ is attributed to the transition state whereas the concave upward curve was observed for the substituents in the benzaldehyde moiety and in the combination of aniline and benzaldehyde moieties, and a suitable mechanism was proposed.
Highly active and selective synthesis of imines from alcohols and amines or nitroarenes catalyzed by Pd/DNA in water with dehydrogenation
Tang, Lin,Sun, Huayin,Li, Yunfeng,Zha, Zhenggen,Wang, Zhiyong
, p. 3423 - 3428 (2013/01/16)
A direct imination was developed from alcohols and amines under catalysis of Pd/DNA by dehydrogenation without additional oxidant, affording the corresponding imines in moderate to good yields with excellent chemoselectivity. By virtue of the liberated molecular hydrogen, the nitroarenes could also be deoxidized in situ into amines and a one-pot tandem synthesis of imines was achieved from nitroarenes. This heterogeneous catalyst can be recovered and reused at least five times by taking advantage of its water-soluble reversibility. All these conformations were performed smoothly in water under mild conditions, and an atom economical and environmentally benign synthesis was embodied in this imination.
Cerium(III)-catalyzed synthesis of schiff bases: A green approach
Ravishankar, Lakshmy,Patwe, Siddhartha A.,Gosarani, Nehal,Roy, Aparajita
experimental part, p. 3177 - 3180 (2010/12/24)
The reaction of primary aromatic amines with aryl aldehydes is found to be catalyzed by cerium chloride heptahydrate under solvent-free conditions to give the corresponding Schiff bases in good yields. Copyright Taylor & Francis Group, LLC.
Facile and efficient method for preparation of Schiff bases catalyzed by P2O5/SiO2 under free Solvent conditions
Naeimi, Hossein,Sharghi, Hashem,Salimi, Fariba,Rabiei, Khadijeh
, p. 43 - 47 (2008/03/30)
A simple and convenient method for the preparation of Schiff bases is developed. In this method, the Schiff base compounds were prepared from the reaction of carbonyl compounds with primary amines. In this reaction, P 2O5/SiO2 have catalyzed the Schiff base formation in dry media under solvent-free conditions. Advantages of this method are use of an inexpensive and efficient catalyst, high yields of products, short reaction times, and simplicity of the reaction and workup.
General acid-catalyzed addition of methanol to (E)-N-benzylideneanilines
Bennour,Toullec
, p. 760 - 773 (2007/10/03)
The reaction of equilibrium addition of methanol (α-amino ether formation) to benzylideneanilines (C6H5CH=NC6H4Y, with Y = H (1a), 3-Cl (1b), 3-NO2 (1c), 4-CN (1d), and 4-NO2(1e)) in methanol is shown to be general acid-catalyzed in carboxylic acid buffers. The mechanism involves fast iminium ion formation followed by base-assisted addition of methanol. The α Bronsted exponents are in the 0.67-0.88 range, and α increases with the electron-withdrawing ability of Y. The same mechanism is valid for MeOH2/+-catalysis, meaning that two solvent molecules are involved in the addition process, one of them playing the role of base. The equilibrium constant, K, is increased by electron-withdrawing substituents, log K depending linearly on the σ- substituent parameters. The substituent effects on the forward and reverse catalytic rate constants are analyzed by means of the log k = ρ(n)σ(n) + ρ(r)(σ- - σ(n)) + constant (Young-Jencks) equation. For carboxylic acid catalysis, the ρ(n) and ρ(r) parameters are in keeping with ca. half C - O bond forming or breaking at the transition state. The catalytic rate constants and α exponent for elimination of ClCH2CH2OH in methanol from the C6H5CH(OCH2CH2,Cl)NH(4-CNC6H4) chloroethyl adduct are compared with those for the elimination of methanol from C6H5CH(OCH3)NH(4-CNC6H4). The chloromethyl group makes the reaction slower and α lower. This indicates that proton transfer is a little ahead of C - O bond cleavage at the transition state. Y substituent effects, α values, and the effects of the CH'2C'l group are interpreted on the basis of a More O'Ferrall - Jencks diagram.
