705-60-2Relevant articles and documents
Active Base Hybrid Organosilica Materials based on Pyrrolidine Builder Units for Fine Chemicals Production
Llopis, Sebastián,Velty, Alexandra,Díaz, Urbano
, p. 5012 - 5024 (2021/10/19)
The catalytic activity of “pyrrolidine type” fragments included or anchored in the mesoporous silica supports or polymeric frameworks have been fully reported for enantioselective transformation. Nevertheless, low attention was focused on their catalytic abilities to perform base-catalyzed reaction. Accordingly, hybrid materials including pyrrolidine fragments in the mesoporous silica supports were prepared following different synthesis methods, such as micellar and fluoride sol-gel routes in absence of structural directing agents. Their great catalytic performance was explored for various base-catalyzed reactions to the formation of C?C bond through Knoevenagel, Claisen-Schmidt and Henry condensations under microwave irradiation. The benefits of microwave irradiation combined with suitable catalytic properties of pyrrolidine hybrid materials with strong base sites and high accessibility to active centers, allowed carrying out successfully base-catalyzed condensation reactions for the production of fine chemicals. Moreover, the hybrid catalyst exhibited high selectivity and good stability over different catalytic cycles contributing to environmental sustainability.
Diindenopyrazines: Electron-Deficient Arenes
Brosius, Victor,Bunz, Uwe H. F.,Freudenberg, Jan,Hippchen, Nikolai,Rominger, Frank,Weigold, Svenja
supporting information, p. 10001 - 10005 (2021/06/07)
The syntheses, properties and application of the air-stable electron acceptors, diindenopyrazines 4 a–g are reported demonstrating the introduction of functional aryl groups in the 6- and 12-positions. The targets are accessible on the hundred milligram to gram scale. The structure of the aryl groups in 4 a–g modulates their solubility, redox potentials and optical properties. The introduction of electron-poor aryl groups to the electron-poor diindenopyrazine backbone reduces the electron affinity to ?4 eV, making the compounds attractive as n-semiconductors. A simple organic field-effect transistor of 4 e –without optimization– shows electron transport with a mobility of up to 0.037 cm2 V?1 s?1.
Dipolar HCP materials as alternatives to DMF solvent for azide-based synthesis
Bai, Rongxian,Gao, Feng,Gu, Yanlong,Li, Minghao
supporting information, p. 7499 - 7505 (2021/10/12)
Hypercrosslinked polymers HCP-DMF and HCP-DMF-SO3H containing abundant and flexible DMF moieties were designed and synthesized. Benefitting from the solvation microenvironment provided by the pseudo-DMF moities, the polar HCPs manifested outstanding performances in the conversions of NaN3 to benzylic azides and 1,2,3-triazoles in EtOH (95%), respectively, avoiding the use of risky DMF and improving the separation processes of the products.
Ionic-Liquid Controlled Nitration of Double Bond: Highly Selective Synthesis of Nitrostyrenes and Benzonitriles
Casiello, Michele,Caputo, Daniela,Fusco, Caterina,Cotugno, Pietro,Rizzi, Vito,Dell'Anna, Maria Michela,D'Accolti, Lucia,Nacci, Angelo
supporting information, p. 6012 - 6018 (2020/08/24)
Unprecedented in literature, the conversion of aryl alkenes into β-nitrostyrenes (2) or benzonitriles (3) with sodium nitrite can be governed by an appropriate choice of ionic liquid (IL) medium. A general trend was found for the selectivity of these processes, which depends on the nature of IL, with imidazolium-based ILs, such as [Bmim]Cl, that favor the C–H nitration leading to β-nitrostyrenes, while tetraalkylammonium-based ILs, such as TBAA, privilege the C=C bond cleavage affording benzonitriles. Besides a substrate scope, mechanistic hypotheses were provided on the origin of the different selectivity in the two kinds of ILs, based on their own tunable properties such as polarity, viscosity, and solvent cage effects.
A diversity-oriented synthesis of polyheterocycles: Via the cyclocondensation of azomethine imine
Ansari, Arshad J.,Pathare, Ramdas S.,Kumawat, Anita,Maurya, Antim K.,Verma, Sarika,Agnihotri, Vijai K.,Joshi, Rahul,Metre, Ramesh K.,Sharon, Ashoke,Pardasani,Sawant, Devesh M.
supporting information, p. 13721 - 13724 (2019/09/16)
Pd-Catalyzed sequential reactions to afford skeletally diverse molecules are described. The reaction involved azomethine imine formation and a cyclocondensation reaction as individual steps. The methodology provides excellent regio- and stereocontrol. Skeletal diversity was ensured by changing the electrophilic counterpart of azomethine imine. Due to its broader diversity and complexity, the DOS methodology is likely to benefit drug discovery and development in the future.
Substrate promiscuity of ortho-naphthoquinone catalyst: Catalytic aerobic amine oxidation protocols to deaminative cross-coupling and n-nitrosation
Kim, Hun Young,Oh, Kyungsoo,Si, Tengda
, p. 9216 - 9221 (2019/10/08)
ortho-Naphthoquinone-based organocatalysts have been identified as versatile aerobic oxidation catalysts. Primary amines were readily cross-coupled with primary nitroalkanes via deaminative pathway to give nitroalkene derivatives in good to excellent yields. Secondary and tertiary amines were inert to ortho-naphthoquinone catalysts; however, secondary nitroalkanes were readily converted by ortho-naphthoquinone catalysts to the corresponding nitrite species that in situ oxidized the amines to the corresponding N-nitroso compounds. Without using harsh oxidants in a stoichiometric amount, the present catalytic aerobic oxidation protocol utilizes the substrate promiscuity feature to provide a facile access to amine oxidation products under mild reaction conditions.
A Deprotonation Approach to the Unprecedented Amino-Trimethylenemethane Chemistry: Regio-, Diastereo-, and Enantioselective Synthesis of Complex Amino Cycles
Trost, Barry M.,Wang, Youliang
supporting information, p. 11025 - 11029 (2018/07/30)
The first realization of the amino-trimethylenemethane chemistry is reported using a deprotonation strategy to simplify the synthesis of the amino-trimethylenemethane donor in two steps from commercial and inexpensive materials. A broad scope of cycloaddition acceptors (seven different classes) participated in the chemistry, chemo-, regio-, diastereo-, and enantioselectively generating various types of highly valuable complex amino cycles. Multiple derivatization reactions that further elaborated the initial amino cycles were performed without isolation of the crude product. Ultimately, we applied the amino-trimethylenemethane chemistry to synthesize a potential pharmaceutical in 8 linear steps and 7.5 % overall yield, which previously was achieved in 18 linear steps and 0.6 % overall yield.
Catalyst- and Substituent-Controlled Switching of Chemoselectivity for the Enantioselective Synthesis of Fully Substituted Cyclobutane Derivatives via 2 + 2 Annulation of Vinylogous Ketone Enolates and Nitroalkene
Akula, Pavan Sudheer,Hong, Bor-Cherng,Lee, Gene-Hsiang
supporting information, p. 7835 - 7839 (2019/01/04)
The first regioselective, diastereoselective, and enantioselective organocatalyzed Michael-Michael cascade of vinylogous ketone enolates and nitroalkenes for the construction of fully substituted cyclobutanes is achieved by the deployment of the appropriate chiral squaramide catalyst and the pertinent substituent on the substrate. The domino reaction provided cyclobutanes with four contiguous stereocenters, including a quaternary center in good yields with diastereomeric ratio of >20:1 and with enantioselectivities of mostly up to 98% enantiomeric excess (ee). The structures and the absolute configurations of the adducts were confirmed by single-crystal X-ray crystallographic analyses of the appropriate products.
Synthesis, antiproliferative and pro-apoptotic effects of nitrostyrenes and related compounds in Burkitt’s lymphoma
Byrne, Andrew J.,Bright, Sandra A.,Fayne, Darren,McKeown, James P.,McCabe, Thomas,Twamley, Brendan,Williams, Clive,Meegan, Mary J.
, p. 181 - 199 (2018/03/13)
Background: Cancers of the lymphatic cells (lymphomas) account for approximately 12% of malignant diseases worldwide. The nitrostyrene scaffold is identified as a lead target structure for the development of particularly effective compounds targeting Burkitt’s lymphoma (BL). Objectives: The aims of the curent study were to synthesise a panel of nitrostyrene compounds and to evaluate their activity in Burkitt’s lymphoma (BL). Methods: A panel of structurally varied compounds were designed and synthesised using Henry Knoevenagel condensation reactions. Single crystal X-Ray analysis confirmed the E configuration for six examples of these novel structures. A number of nitrostyrene-related compounds were also investigated including 1,3-bis(aryl)-2-nitropropenes together with heterocyclic scaffolds containing the nitrovinyl pharmacophore such as 3-nitro-2-phenyl-2H-chromenes. The antiproliferative activities of the compounds were evaluated using the BL cell lines EBV- MUTU-1 and EBV+ DG-75 (chemoresistant) to establish preliminary structure-activity relationships. Results: Lead compounds with optimized nitrostyrene scaffolds and 3-nitro-2-phenyl-2Hchromene structures were successfully established with typical IC50 values of 0.45 μM and 0.47 μM in MUTU-1 cells and 1.41 μM and 1.92 μM, respectively, in DG-75 cells. The mechanism of cell death was identified as apoptotic and the lead compound was found to elicit comparable apoptotic effects to Taxol in Burkitt’s lymphoma cell lines MUTU-1 and DG-75. Conclusion: This class of pharmaceutically active compounds with potential for the treatment of Burkitt’s lymphoma suggest a potential role for nitrostyrene based agents in chemotherapy.
Electronic effect of substituents on anilines favors 1,4-addition to: Trans -β-nitrostyrenes: Access to N -substituted 3-arylindoles and 3-arylindoles
Gattu, Radhakrishna,Bhattacharjee, Suchandra,Mahato, Karuna,Khan, Abu T.
supporting information, p. 3760 - 3770 (2018/05/30)
A simple and an efficient method for the regioselective synthesis of N-alkyl/aryl/H 3-arylindole derivatives from N-substituted anilines and trans-β-nitrostyrenes has been described using 10 mol% of bismuth(iii) triflate as a catalyst in acetonitrile at 80 °C. The present protocol profits from the formation of new C-C and C-N bonds, broad substrate scope and moderate to good yields.
