1754-62-7Relevant academic research and scientific papers
Photodimerization of hydrophobic guests within a water-soluble nanocapsule
Parthasarathy, Anand,Samanta, Shampa R.,Ramamurthy
, p. 73 - 87 (2013)
Conducting reactions in environmentally benign conditions is one of the major objectives of "green chemistry." In this context, developing ways to conduct reactions in water seems obvious. In this report, we present our results on photodimerization of sel
Stereospecific (2π+2π) photocycloaddition of arylalkenes to pyrene via exciplex: Formation of 1:1- and 2:1-cycloadducts
Mizuno, Kazuhiko,Maeda, Hajime,Inoue, Yohtaro,Sugimoto, Akira,Vo, Luc P.,Caldwell, Richard A.
, p. 4913 - 4916 (2000)
Irradiation of benzene solutions containing pyrene and electron- deficient arylalkenes such as E- and Z-methyl cinnamates afforded (2π+2π) photocycloadducts including 1:2-cycloadduct in high yields in a stereospecific and endo-selective manner. Sandwich-type singlet exciplexes between pyrene and arylalkenes were proposed as reactive intermediates. (C) 2000 Elsevier Science Ltd.
A Straightforward, Purification-Free Procedure for the Synthesis of Ando and Still-Gennari Type Phosphonates
Janicki, Ignacy,Kie?basiński, Piotr
, p. 378 - 382 (2021/10/21)
Z-Selective Still-Gennari and Ando modifications of the typically E-selective Horner-Wadsworth-Emmons reaction are highly valuable synthetic tools in organic chemistry. These procedures are based on application of bis(2,2,2-trifluoroethyl) phosphonates or diaryl phosphonates, respectively, for the olefination of carbonyl groups. In our research, we present an improved, straightforward, purificationfree procedure for the synthesis of these reagents. The key step of our procedure is the reaction of phosphonic dichlorides with the appropriate sodium alkoxides, which results in 52-97% isolated yields of the desired products on a gram scale. The whole three-step process is performed in one pot. Most importantly, the product is obtained in over 95% purity after simple extraction, avoiding column chromatography and distillation. Moreover, we present the synthesis of a novel Still-Gennari type reagent, bis(1,1,1,3,3,3-hexafluoroisopropyl) phosphonates, which may exhibit improved Z-selectivity in Still-Gennari olefinations.
Synthesis of α-diazoesters from α-hydrazonoesters: Utilization of α-hydrazonoesters and α-diazoesters for convenient interconversion
Yasui, Eiko,Ishimine, Kanako,Nitanai, Sohta,Hatakeyama, Nanami,Nagumo, Shinji
, (2022/04/07)
We have developed a novel method to synthesize α-diazoesters from α-hydrazonoesters with a catalytic amount of Cu(OAc)2 in acetonitrile. When the reaction was carried out under an argon atmosphere, the reaction stopped halfway, suggesting that this reaction required oxygen to reoxidize the catalyst. Since hydrazonoesters can be obtained by reduction of α-diazoesters with P(n-Bu)3 in diisopropyl ether, these 2 compounds are mutually interconvertible with ease. Whereas α-diazoesters are unstable and unsuitable for storage, hydrazonoesters are more stable, especially crystalline hydrazonoesters. Thus, hydrazonoesters, which are suitable for long-term storage, could be conveniently used as precursors for α-diazoesters.
Visible-Light-Driven Isocyanide Insertion to o-Alkenylanilines: A Route to Isoindolinone Synthesis
Dahiya, Anjali,Das, Bubul,Sahoo, Ashish Kumar,Patel, Bhisma K.
, p. 966 - 973 (2022/02/07)
A visible-light-mediated intermolecular radical insertion of isocyanides to electron-deficient o-alkenylanilines leading to isoindolinone is reported. Deuterium (D2O) and H2O18 labelling experiments suggest H and O incorporation in the product. The formation of an N-centered radical (NCR) via stepwise PT/ET process was confirmed by radical trapping experiments, photoluminescence, cyclic voltammetry and DFT studies. This photo cascade methodology is overall a redox neutral process featuring metal-free condition and broad substrate scope (32 examples). The synthesis of analogue of GABA receptor antagonist shows the practical utility of this method. (Figure presented.).
Electrochemical Proton Reduction over Nickel Foam for Z-Stereoselective Semihydrogenation/deuteration of Functionalized Alkynes
Valiente, Alejandro,Martínez-Pardo, Pablo,Kaur, Gurpreet,Johansson, Magnus J.,Martín-Matute, Belén
, (2021/12/22)
Selective reduction strategies based on abundant-metal catalysts are very important in the production of chemicals. In this paper, a method for the electrochemical semihydrogenation and semideuteration of alkynes to form Z-alkenes was developed, using a simple nickel foam as catalyst and H3O+ or D3O+ as sources of hydrogen or deuterium. Good yields and excellent stereoselectivities (Z/E up to 20 : 1) were obtained under very mild reaction conditions. The reaction proceeded with terminal and nonterminal alkynes, and also with alkynes containing easily reducible functional groups, such as carbonyl groups, as well as aryl chlorides, bromides, and even iodides. The nickel-foam electrocatalyst could be recycled up to 14 times without any change in its catalytic properties.
Pd-Catalyzed desulfitative arylation of olefins by: N -methoxysulfonamide
Ojha, Subhadra,Panda, Niranjan
supporting information, p. 1292 - 1298 (2022/02/19)
A novel Pd-catalyzed protocol for the desulfitative Heck-type reaction of N-methoxy aryl sulfonamides with alkenes was reported. The cross-coupling reaction was performed successfully with a variety of olefins to obtain aryl alkenes. Different substituents on the aromatic ring of N-methoxysulfonamides were also found to be compatible with the reaction conditions. Expectedly, the reaction proceeds through CuCl2-promoted generation of the nitrogen radical and subsequent desulfonylation under thermal conditions to afford the aryl radical for the Pd-catalyzed coupling reaction. N-Methoxysulfonamide was further exploited for the synthesis of symmetrical biaryls in the presence of CuCl2. This journal is
Synthesis of novel 1-phenyl-benzopyrrolizidin-3-one derivatives and evaluation of their cytoneuroprotective effects against NMDA-induced injury in PC12 cells
Cao, Jiafu,Li, Qiji,Liao, Xiu,Wang, Enhua,Wang, Li,Yang, Juan,Yang, Lishou,Yang, Qian,Yang, Xiaosheng,Yang, Yan
supporting information, (2022/02/23)
A range of novel 1-phenyl-benzopyrrolizidin-3-one derivatives were synthesized and evaluated for neuroprotective effects against N-methyl-?-aspartate (NMDA)-induced injury in PC12 cells. Interestingly, derivatives that 1-phenyl moiety bearing electron-donating group, especially benzyloxy, and the trans-forms exhibited better protective activity against NMDA-induced neurotoxicity. Compound 11 m demonstrated the best neuroprotective potency and shown a dose-dependent prevention. The increased intracellular calcium (Ca2+) influx caused by NMDA in PC12 cells was reversed in the case of compound 11 m pretreatment at 15 μM. These results suggested that the synthesized 1-phenyl-benzopyrrolizidin-3-one derivatives exerted neuroprotective effect on NMDA-induced excitotoxicity in PC12 cells associated with inhibition of Ca2+ overload and can be further optimized for the development of neuroprotective agents.
Click amidations, esterifications and one–pot reactions catalyzed by Cu salts and multimetal–organic frameworks (M–MOFs)
Armentano, Donatella,Ferrando-Soria, Jesús,Greco, Rossella,Leyva-Pérez, Antonio,Palomar-De Lucas, Brenda,Pardo, Emilio,Tiburcio, Estefanía
, (2022/03/17)
Amides and esters are prevalent chemicals in Nature, industry and academic laboratories. Thus, it is not surprising that a plethora of synthetic methods for these compounds has been developed along the years. However, these methods are not 100% atom economical and generally require harsh reagents or reaction conditions. Here we show a “spring–loaded”, 100% atom–efficient amidation and esterification protocol which consists in the ring opening of cyclopropenones with amines or alcohols. Some alkyl amines react spontaneously at room temperature in a variety of solvents and reaction conditions, including water at different pHs, while other alkyl amines, aromatic amines and alcohols react in the presence of catalytic amounts of simple Cu2+ salts or solids. A modular reactivity pattern (alkyl amines >> alkyl alcohols >> phenols >> aromatic amines) enables to design orthogonal and one–pot reactions on well–defined catalytic Multimetal–Organic Frameworks (M–MOFs, M= Cu, Ni, Pd), to easily functionalize the resulting cinnamides and cinnamic esters to more complex molecules. The strong resemblance of the amidation and esterification reaction conditions here reported with the copper–catalyzed azide–alkyne cycloaddition (CuAAC) allows to define this fast, clean and flexible protocol as a click reaction.
Exploring the synthetic potential of a marine transaminase including discrimination at a remote stereocentre
Schwarz, Maria,Murphy, Edel J.,Foley, Aoife M.,Woods, David F.,Castilla, Ignacio Abreu,Reen, F. Jerry,Collins, Stuart G.,O'gara, Fergal,Maguire, Anita R.
supporting information, p. 188 - 198 (2021/01/18)
The marine transaminase, P-ω-TA, can be employed for the transamination from 1-aminotetralins and 1-aminoindanes with differentiation of stereochemistry at both the site of reaction and at a remote stereocentre resulting in formation of ketone products with up to 93% ee. While 4-substituents are tolerated on the tetralin core, the presence of 3- or 8-substituents is not tolerated by the transaminase. In general P-ω-TA shows capacity for remote diastereoselectivity, although both the stereoselectivity and efficiency are dependent on the specific substrate structure. Optimum efficiency and selectivity are seen with 4-haloaryl-1-aminotetralins and 3-haloaryl-1-aminoindanes, which may be associated with the marine origin of this enzyme. This journal is
