588-68-1Relevant articles and documents
N-Amino-1,8-Naphthalimide is a Regenerated Protecting Group for Selective Synthesis of Mono-N-Substituted Hydrazines and Hydrazides
Manoj Kumar, Mesram,Venkataramana, Parikibanda,Yadagiri Swamy, Parikibanda,Chityala, Yadaiah
supporting information, p. 17713 - 17721 (2021/11/10)
A new route to synthesis of various mono-N-substituted hydrazines and hydrazides by involving in a new C?N bond formation by using N-amino-1,8-naphthalimide as a regenerated precursor was invented. Aniline and phenylhydrazines are reproduced upon reacting these individually with 1,8-naphthalic anhydride followed by hydrazinolysis. The practicality and simplicity of this C?N dihalo alkanes; developed a synthon for bond formation protocol was exemplified to various hydrazines and hydrazides. N-amino-1,8-naphthalimide is suitable synthon for transformation for selective formation of mono-substituted hydrazine and hydrazide derivatives. Those are selective mono-amidation of hydrazine with acid halides; mono-N-substituted hydrazones from aldehydes; synthesis of N-aminoazacycloalkanes from acetohydrazide scaffold and inserted to hydroxy derivatives; distinct synthesis of N,N-dibenzylhydrazines and N-benzylhydrazines from benzyl halides; synthesis of N-amino-amino acids from α-halo esters. Ecofriendly reagent N-amino-1,8-naphthalimide was regenerated with good yields by the hydrazinolysis in all procedures.
Ruthenium(ii)-catalysed 1,2-selective hydroboration of aldazines
Gunanathan, Chidambaram,Pradhan, Subham,Thiyagarajan, Subramanian
supporting information, p. 7147 - 7151 (2021/08/30)
Herein, an efficient and simple catalytic method for the selective and partial reduction of aldazines using ruthenium catalyst [Ru(p-cymene)Cl2]2 (1) has been accomplished. Under mild conditions, aldazines undergo the addition of pinacolborane in the presence of a ruthenium catalyst, which delivered N-boryl-N-benzyl hydrazone products. Notably, the reaction is highly selective, and results in exclusive mono-hydroboration and desymmetrization of symmetrical aldazines. Mechanistic studies indicate the involvement of in situ formed intermediate [{(η6-p-cymene)RuCl}2(μ-H-μ-Cl)] (1a) in this selective hydroboration.
Conversion of Ammonia to Hydrazine Induced by High-Frequency Ultrasound
Allavena, Audrey,Amaniampong, Prince N.,Chave, Tony,De Oliveira Vigier, Karine,Grimaud, Laurie,Humblot, Anaelle,Jér?me, Fran?ois,Streiff, Stéphane
supporting information, p. 25230 - 25234 (2021/09/14)
Hydrazine is a chemical of utmost importance in our society, either for organic synthesis or energy use. The direct conversion of NH3 to hydrazine is highly appealing, but it remains a very difficult task because the degradation of hydrazine is thermodynamically more feasible than the cleavage of the N?H bond of NH3. As a result, any catalyst capable of activating NH3 will thus unavoidably decompose N2H4. Here we show that cavitation bubbles, created by ultrasonic irradiation of aqueous NH3 at a high frequency, act as microreactors to activate and convert NH3 to NH species, without assistance of any catalyst, yielding hydrazine at the bubble–liquid interface. The compartmentation of in-situ-produced hydrazine in the bulk solution, which is maintained close to 30 °C, advantageously prevents its thermal degradation, a recurrent problem faced by previous technologies. This work also points towards a path to scavenge .OH radicals by adjusting the NH3 concentration.
Potassium tert -Butoxide Promoted Synthesis of 4,5-Diaryl-2 H -1,2,3-triazoles from Tosylhydrazones and Nitriles
Qiu, Shanguang,Chen, Yuxue,Song, Xinming,Liu, Li,Liu, Xi,Wu, Luyong
, p. 86 - 90 (2020/11/02)
Intermolecular cycloaddition of tosylhydrazones with nitriles was investigated. t -BuOK was shown to be an excellent base for increasing the effectiveness of the reaction in this protocol, and homocoupling of the tosylhydrazones was significantly inhibited by using xylene as a solvent. Through this transformation, a variety of 4,5-diaryl-2 H -1,2,3-triazoles were prepared in good to excellent yields and with high purities. The process is azide-free and transition-metal-free.
Azine based AIEgens with multi-stimuli response towards picric acid
Pavithra, Kumaravelu,Sathiyaraj, Munusamy,Thiagarajan, Viruthachalam
supporting information, p. 8402 - 8411 (2020/06/09)
Multifunctional aggregation induced emission luminogens (AIEgens) are novel materials which have significant applications in various fields including biomedical, optoelectronics and sensors. Enormous efforts have been directed towards the strategic development and characterisation of AIEgens, in order to better understand the AIE mechanism. Herein, we studied the photophysical properties of symmetrical azine (D-π-D) based AIEgens in detail by varying the solvent polarity and viscosity. The AIE behaviour of the azine derivatives relies on the substituents on the nitrogen atom of the amine moiety. Further, these azine derivatives sense the picric acid (PA) with high selectivity and sensitivity in both monomer and aggregated forms. The hydrogen bonding interaction of PA with any one side of the amine nitrogen leads to the formation of a new intramolecular charge transfer state which results in the formation of new absorption and emission spectra. Interestingly in the presence of PA, azine monomers exhibit fluorescence enhancement in pure THF, while aggregated azine molecules show fluorescence quenching in THF-water mixtures.
Traceless Isoprenylation of Aldehydes via N-Boc-N-(1,1-dimethylallyl)hydrazones
Heerdegen, Desirée,Junker, Julia,Dittrich, Sebastian,Mayer, Peter,Bracher, Franz
, p. 3680 - 3687 (2020/06/02)
A short isoprenylation protocol starting from non-conjugated N-Boc-N-(1,1-dimethylallyl)hydrazones was developed utilising Thomson's traceless bond construction. This type of [3,3]-sigmatropic rearrangement is catalysed by the Br?nsted acid triflimide and liberates only gaseous by-products. The required N-Boc-N-allylhydrazine precursor is available in three steps starting from a known diazene using biocatalytic aldol addition and Tebbe olefination as key steps. Allylhydrazones are prepared via condensation with appropriate aldehydes. Scope and limitations of the [3,3]-sigmatropic rearrangements are analysed.
Glucose:urea:NH4Cl low melting mixture for the synthesis of symmetric azines
Theresa, Letcy V.,Shaibuna,Sreekumar
, p. 3148 - 3160 (2019/09/03)
Alternate reaction media have become very important due to the problems created by the highly volatile nature of the solvents. The deep eutectic mixture is a kind of an alternate reaction medium which has emerged in recent years. Low melting mixtures were introduced by making the deep eutectic mixture more cost-effective and renewable by introducing carbohydrates into it. The properties of low melting mixtures include easiness to prepare, usage of low-cost components, biodegradability, solubility in water, easy separation from organic compounds, etc. The low melting mixtures such as glucose:urea:NH4Cl, glucose:ChCl, glucose:urea:ChCl, glycerol:urea:NH4Cl, and ethylene glycol:urea:NH4Cl were used in different ratios for the reactions. The properties such as viscosity, density, acidity, glass transition temperature, and thermal stability were studied. An unusual method for the synthesis of symmetrical azines is introduced wherein benzaldehyde and hydroxylamine are reacted in the presence of glucose:urea:NH4Cl. The method of synthesis needs only less reaction time, temperature and the product was easily separated. The products were confirmed using GC-MS and NMR techniques. The recyclability of glucose:urea:NH4Cl was studied.
Dihydrazone compound high in affinity with Abeta protein and Tau protein, derivative thereof, and applications of dihydrazone compound and derivative
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Paragraph 0029-0031, (2019/05/15)
The invention provides a dihydrazone compound high in affinity with Abeta protein and Tau protein, a derivative thereof, and applications of the dihydrazone compound and the derivative. The structureof the dihydrazone compound is represented by formula I. The dihydrazone compound can be directly taken as a fluorescence probe used for detecting neurofibrillary tangles in vivo or in tissue samples;when the dihydrazone compound is adopted in nuclear medicine imaging, appropriate radioisotopes are needed for labeling. The dihydrazone compound is especially suitable to be used for diagnosis of neurodegenerative diseases, and diagnosis of patients with diseases with Abeta plaques including Alzheimer's disease.
Scalable Wolff-Kishner Reductions in Extreme Process Windows Using a Silicon Carbide Flow Reactor
Znidar, Desiree,O'Kearney-Mcmullan, Anne,Munday, Rachel,Wiles, Charlotte,Poechlauer, Peter,Schmoelzer, Christoph,Dallinger, Doris,Kappe, C. Oliver
supporting information, p. 2445 - 2455 (2019/11/03)
A safe and scalable continuous flow strategy for Wolff-Kishner reductions that employs methanol as the solvent has been developed. The use of low-cost hydrazine as the reducing agent in combination with a caustic base provides an atom-efficient, environmentally friendly method for the deoxygenation of aldehydes and ketones to alkanes. Because of the required harsh and corrosive reaction conditions (200 °C, 50 bar), reactor materials such as stainless steel, glass, or any type of polymer have compatibility problems, rendering this process problematic on a production scale. The use of corrosion-resistant silicon carbide (SiC) as the reactor material opens up the possibility of performing Wolff-Kishner reductions on scale with a considerably improved safety profile. Methanol as the solvent significantly simplifies the workup procedure compared with the generally employed high-boiling solvents such as diethylene glycol. The continuous flow protocol was applied to a number of substrates and provided the desired products in good to high yields with space-time yields of up to 152 g L-1 h-1. In addition, a pharmaceutically valuable active pharmaceutical ingredient precursor was synthesized by employing this higherature/pressure Wolff-Kishner protocol.
Unprecedented synthesis of symmetrical azines from alcohols and hydrazine hydrate using nickel based NNN-pincer catalyst: An experimental and computational study
Shiekh, Bilal Ahmad,Kaur, Damanjit,Godara, Sachin Kumar
, p. 19 - 23 (2019/03/02)
Azines are having widespread applications in both industry as well as synthetic chemistry. Thus new catalytic synthetic protocols are desirable as they are greener alternatives than traditional methods of synthesis. Thus, herein a novel earth abundant nickel based NNN-pincer catalyst Ni(BPEA)(Cl2) is synthesized for the first time for the direct transformation of alcohols and hydrazine hydrate into symmetrical azines. This catalytic reaction is accompanied by dehydrogenative coupling of alcohols and hydrazine hydrate and is carried out in presence of a base. Theoretical calculations supported by experimental evidence have been performed for understanding the mechanistic insights of the reaction.
