122-01-0Relevant articles and documents
A General Cp*CoIII-Catalyzed Intramolecular C?H Activation Approach for the Efficient Total Syntheses of Aromathecin, Protoberberine, and Tylophora Alkaloids
Lerchen, Andreas,Knecht, Tobias,Koy, Maximilian,Daniliuc, Constantin G.,Glorius, Frank
, p. 12149 - 12152 (2017)
Herein, we report a Cp*CoIII-catalyzed C?H activation approach as the key step to create highly valuable isoquinolones and pyridones as building blocks that can readily be applied in the total syntheses of a variety of aromathecin, protoberberine, and tylophora alkaloids. This particular C?H activation/annulation reaction was achieved with several terminal as well as internal alkyne coupling partners delivering a broad scope with excellent functional group tolerance. The synthetic applicability of this protocol reported herein was demonstrated in the total syntheses of two Topo-I-Inhibitors and two 8-oxyprotoberberine cores that can be further elaborated into the tetrahydroprotoberberine and the protoberberine alkaloid core. Moreover these building blocks were also transformed to six different tylophora alkaloids in expedient fashion.
Synthesis of N-[4-(alkyl)cyclohexyl]-substituted benzamides with anti-inflammatory and analgesic activities
Pau, Amedeo,Boatto, Gianpiero,Palomba, Michele,Asproni, Battistina,Cerri, Riccardo,Palagiano, Francesco,Filippelli, Walter,Falcone, Giuseppe,Motola, Giulia
, p. 524 - 532 (1999)
Two series of N-[4-(alkyl)cyclohexyl]-substituted benzamides, i.e. a series of N-[4-(tert-butyl)cyclohexyl]-substituted benzamides and a series of N-[4-(ethyl)cyclohexyl]-substituted benzamides, were synthesised and evaluated for their anti-inflammatory and analgesic potencies, and gastrointestinal irritation liability. Copyright (C) 1999 Elsevier Science S.A.
Equilibrium and Dynamic Dielectric Properties of Acrylate Polymers with (Phenyl)(4-chlorophenyl)methanone Groups in Their Structure
Nunes, R.C.,Diaz-Calleja, R.,Pinto, M.,Saiz, E.,Riande, E.
, p. 12962 - 12970 (1995)
The curves describing the relaxation behavior of poly(4-(acryloxy)phenyl)(4-chlorophenyl)methanone at several frequencies present in the dielectric loss-temperature plane a β relaxation centered at -76 deg C at 10 Hz, whose activation energy shows a slight tendency to increase as the temperature goes up.The relaxation spectra exhibit an ostensible glass-rubber relaxation or α process centered at 106 deg C at 10 Hz, in which free charge conductivity and blocking electrode phenomena become dominant at frequencies below 10 Hz.An electric model is used to separate the dipolar response from conductivity contributions in the glass-rubber relaxation, and the dipole time correlation function for this process is obtained at several temperatures.The intramolecular correlation coefficient gintra, determined from dielectric measurements in solution, is somewhat larger than the coefficient g involving both intra- and intermolecular interactions, obtained from dielectric measurements in the bulk.A rotational state scheme is developed which gives a good account of the intramolecular dipolar correlation coefficient.Finally whereas the relaxation mechanisms involved in the glass-rubber relaxation seem to be governed by the volume, the conductive processes exhibit Arrhenius behavior.
Immobilization of (l)-valine and (l)-valinol on SBA-15 nanoporous silica and their application as chiral heterogeneous ligands in the Cu-catalyzed asymmetric allylic oxidation of alkenes
Samadi, Saadi,Ashouri, Akram,Rashid, Hersh I,Majidian, Shiva,Mahramasrar, Mahsa
supporting information, p. 17630 - 17641 (2021/10/04)
SBA-15 nanoporous silica was synthesized by hydrothermal method using P123 surfactant and tetraethoxyortosilicate in acidic condition and then functionalized by 3-chloropropyltrimethoxysilane. Next, by immobilization of chiral amino acid (S)-2-amino-3-methyl butanoic acid (l-valine) and chiral amino alcohol (S)-2-amino-3-methylbutane-1-ol (l-valinol), preparedviathe reduction ofl-valine by NaBH4/I2in THF, on functionalized-SBA-15, chiral heterogeneous ligands AL*-i-Pr-SBA-15 and AA*-i-Pr-SBA-15 were prepared and characterized by FT-IR, XRD, TGA, EDX, SEM, BET-BJH techniques. The asymmetric allylic oxidation of alkenes was done using copper-complexes of these ligands and the as-synthesized peresters. The reactions were optimized by varying various parameters such as temperature, solvent, amount of chiral heterogeneous ligand, as well as the type and amount of copper salt. Under optimized conditions, 6 mg of AL*-i-Pr-SBA-15 and 3.2 mol% of Cu(CH3CN)4PF6in acetonitrile at 50 °C, the chiral allylic ester was obtained with 80% yield and 39% enantiomeric excess in 24 h. The recyclability of the chiral heterogeneous catalysts was also evaluated without significant reduction in the reaction results up to three runs.
PCl3-mediated transesterification and aminolysis of tert-butyl esters via acid chloride formation
Wu, Xiaofang,Zhou, Lei,Li, Fangshao,Xiao, Jing
, p. 491 - 497 (2021/01/20)
A PCl3-mediated conversion of tert-butyl esters into esters and amides in one-pot under air is developed. This novel protocol is highlighted by the synthesis of skeletons of bioactive molecules and gram-scale reactions. Mechanistic studies revealed that this transformation involves the formation of an acid chloride in situ, which is followed by reactions with alcohols or amines to afford the desired products.