نتایج جستجو برای: cyclocondensation

تعداد نتایج: 265  

Journal: :Journal of advanced scientific research 2022

A N-methyl-2-pyrrolidonium hydrogensulfate [NMP][HSO4] bronsted acidic ionic liquid-promoted cyclocondensation-cyclization pathway has been established using one pot reaction of anilines, aldehydes and mercaptoacetic acid to give 4-thiazolidinone derivatives in good promising yields microwave irradiation. Applications for this protocol are easy workup, high yields, short times, variability func...

Journal: :Chemistry 2013
Mercedes Amat Elena Ghirardi Laura Navío Rosa Griera Núria Llor Elies Molins Joan Bosch

Up to four stereocenters with a well-defined configuration are generated in a single synthetic step by the cyclocondensation of (R)-phenylglycinol or (1S,2R)-1-amino-2-indanol with stereoisomeric mixtures (racemates, meso forms, diastereoisomers) of cyclohexanone-based δ-keto-acid and δ-keto-diacid derivatives in enantio- and diastereoconvergent processes that involve dynamic kinetic resolution...

2017
Patrick T Campos Leticia V Rodrigues Andrei L Belladona Caroline R Bender Juliana S Bitencurt Fernanda A Rosa Davi F Back Helio G Bonacorso Nilo Zanatta Clarissa P Frizzo Marcos A P Martins

The syntheses of several polyazaheterocycles are demonstrated. The cyclocondensation reactions between β-enaminodiketones [CCl3C(O)C(=CNMe2)C(O)-CO2Et] and aromatic amidines resulted in glyoxalate-substituted pyrido[1,2-a]pyrimidinone, thiazolo[3,2-a]pyrimidinone and pyrimido[1,2-a]benzimidazole. Pyrazinones and quinoxalinones were obtained through the reaction of these glyoxalates with ethylen...

Journal: :Dalton transactions 2012
Feng Li Laughlin Arnold L Rheingold Nihal Deligonul Brynna J Laughlin Rhett C Smith Lee J Higham John D Protasiewicz

Seven new fluorescent 2-R-naphtho[2,3-d]oxaphospholes (R-NOPs) (4a–g; R = tBu (a), Ad (b), C(6)H(5) (c), 4-MeC(6)H(4) (d), 4-ClC(6)H(4) (e), 4-BrC(6)H(4) (f ), 4-MeOC(6)H(4) (g)), have been synthesized by cyclocondensation reactions of benzimidoyl chlorides with 3-phosphino-2-naphthol (3). The compounds were characterized by multinuclear NMR, UV-vis, and fluorescence spectroscopy. Compounds 4a–...

Journal: :Organic & biomolecular chemistry 2009
Mohanad Shkoor Abdolmajid Riahi Olumide Fatunsin Ibrar Hussain Mirza A Yawer Mathias Lubbe Stefanie Reim Helmut Reinke Christine Fischer Peter Langer

1-Hydroxy-3,5-dimethyl-2,4-benzodioates (4-hydroxyisophthalates) were prepared by [3+3] cyclocondensation of 1,3-bis(silyloxy)-1,3-butadienes with 3-ethoxycarbonyl-4-trimethylsilyloxy-3-penten-2-one which is synthesized from (symmetrical) ethyl 2-acetylacetoacetate. The [3+3] cyclization of 1,3-bis(silyloxy)-1,3-butadienes with 3-alkoxy-2-alkoxycarbonyl-2-en-1-ones, readily available by reactio...

Mohammad Hosein Farjam

New 1,5-tetra alkyl methyl- phenyl-1H-pyrimido[4,5-e][1,3,4]thiadiazine-3,7-diamine  were synthesized via the cyclocondensation of 2-(5-bromo-2-chloro-6-methylpyrimidin-4-yl)-2-methylhydrazine with phenylthioisothiocyanate  and further replacement of chlorine atom on the seven number position of pyrimido[4, 5- e][1, 3, 4]thiadiazin by appropriate secondary amines  in simple and efficient methods. 

2010
Iraj Mohammadpoor-Baltork Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Zohre Eskandari

An environmentally friendly and highly efficient procedure has been developed for the selective synthesis of 2-aryl-5,6-dihydro-4H-1,3-oxazines and 2-aryl-1,4,5,6-tetrahydropyrimidines by cyclocondensation of arylnitriles with 3-amino-1-propanol and 1,3-diaminopropane in the presence of catalytic amounts of H3PW12O40 under thermal conditions and MW irradiation. Under the same reaction condition...

Journal: :Molecules 2013
Hassan M Faidallah Khalid M A Al-Shaikh Tariq R Sobahi Khalid A Khan Abdullah M Asiri

An efficient and novel method for the synthesis in moderate to good yield (72%-84%) of a series of 3-amino-1-substituted-9,10-dihydrophenanthrene-2,4-dicarbonitriles 1-5 via one-pot multi-component reactions of aldehydes, malononitrile, 1-tetralone and ammonium acetate has been delineated. Cyclocondensation attempts of aminocyanophenanthrene derivatives 1, 2, 4 and 5 with acetic anhydride in th...

2011
Christian Eidamshaus Roopender Kumar Mrinal K Bera Hans-Ulrich Reissig

A practical approach to highly functionalized 4-hydroxypyridine derivatives with stereogenic side chains in the 2- and 6-positions is described. The presented two-step process utilizes a multicomponent reaction of alkoxyallenes, nitriles and carboxylic acids to provide β-methoxy-β-ketoenamides which are transformed into 4-hydroxypyridines in a subsequent cyclocondensation. The process shows bro...

2011
V. V. Dabholkar S. D. Parab

A series of new dicarboxylic acid derivatives of 1,3,4-thiadiazines, 1,4-benzopiperizines, 1,4-thiazines, 1,3-thiazoles, 1,3-oxazoles and 1,3-imidazoles have been synthesized in 80-87% yield by the environmentally benign microwave induced technique involving the cyclocondensation of 2,3-dibromosuccinic acid with 2-aminothiophenol, o-phenylene diamine, 1,2,4-triazole, amidinothiocarbamide, amidi...

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