20000-80-0Relevant academic research and scientific papers
Synthesis and oxidation of some azole-containing thioethers
Potapov, Andrei S.,Chernova, Nina P.,Ogorodnikov, Vladimir D.,Petrenko, Tatiana V.,Khlebnikov, Andrei I.
, p. 1526 - 1532 (2011)
Pyrazole and benzotriazole-containing thioethers, namely 1,5-bis(3,5-dimethylpyrazol-1-yl)-3-thiapentane, 1,8-bis(3,5- dimethylpyrazol-1-yl)-3,6-dithiaoctane and 1,3-bis(1,2,3-benzotriazol-1-yl)-2- thiapropane were prepared and fully characterized. Oxidat
Coordination properties of the didentate N,O ligand 1-(2-hydroxyethyl)-3,5-dimethylpyrazole (HL). Crystal structure of and 2
Driessen, W. L.,Gorter, S.,Haanstra, W. G.,Laarhoven, L. J. J.,Reedijk, J.,et al.
, p. 309 - 313 (1993)
The didentate N,O donor ligand 1-(2-hydroxyethyl)-3,5-dimethylpyrazole (N-hed) renders two kinds of coordination compounds, viz. with M = Co, Ni, Cu, and Zn, , and in which the ligand is neutral, and 2 with X = Cl, Br, and NO3 in which the ligand N-hed is in its deprotonated form, viz. 1-(2-oxidoethyl)-3,5-dimethylpyrazole (N-oed).The crystal structure of shows it to be mononuclear, with the copper ion at a centre of symmetry.Monoclinic, space group P21/c, a = 7.8176(8), b = 14.93(2), c = 8.4076(8) Angstroem, β = 92.62(2) deg, Z = 2; R = 0.036 (Rw=0.038) for 2132 significant reflections.The copper(II) ion is in a tetragonal-distorted, elongated-octahedral environment of two trans pyrazole nitrogen atoms at 1.974(2) Angstroem, two trans hydroxyl oxygen atoms at 1.991(2) Angstroem, and two trans oxygen atoms of monodentate coordinated nitrate anions at 2.561(2) Angstroem.The structure is stabilized by strong intramolecular hydrogen bonds between the hydroxyl group of the coordinated ligand and an oxygen atom of the coordinated nitrate ion with a short O-O distance of 2.599(2) Angstroem.The metal ions in the compounds are octahedrally surrounded by two nitrogen and two oxygen atoms of the ligand and by two anion donor atoms (respectively O, N, or Cl).The crystal structure of 2 shows it to be dinuclear.Triclinic space group P, a = 4.5213(6), b = 8.484(1), c = 13.052(7) Angstroem, α = 81.50(3), β = 85.79(4), γ = 77.79(2) deg, Z = 1, R = 0.148 (RW = 0.224) for 1534 reflections.The copper ions are bridged by two oxo atoms of the deprotonated ligands with a Cu-Cu distance of 3.042(4) Angstroem.Each Cu(II)ion is in a distorted square-planar O2NBr environment.The compounds 2 are diamagnetic and EPR-silent.
Solvent-free synthesis of 3,5-di-tert-butylpyrazole and 3,5-di-substitutedbutylpyrazol-1-ylethanol
Van Wyk, Juanita L.,Omondi, Bernard,Appavoo, Divambal,Guzei, Ilia A.,Darkwa, James
, p. 474 - 477 (2012/10/29)
A high-yield, solvent-free approach to the synthesis of 1,3,5-trisubstituted pyrazoles is reported. Four compounds, (3,5-di-tert-butyl- 1H-pyrazole, (2-(3,5-dimethyl-1H-pyrazol-1-yl)ethanol, 2-(3,5-di-tert-butyl-1H- pyrazol-1-yl)ethanol, 2-(3,5-diphenyl-1
Alkylation of pyrazoles with ethylene chlorohydrin under phase transfer catalysis
Baltayan,Rstakyan,Antanosyan,Kinoyan,Attaryan,Asratyan
experimental part, p. 2417 - 2419 (2010/05/14)
Alkylation reactions of pyrazoles with ethylene chlorohydrin under phase transfer catalysis were studied. Effect of solvent nature on alkylation process was established. 3(5)-Methylpyrazole alkylation products were isolated and identified.
Asymmetric borane reduction of ketones catalyzed by N-hydroxyalkyl-l-menthopyrazoles
Kashima,Tsukamoto,Higashide,Nakazono
, p. 983 - 990 (2007/10/03)
The equimolar mixture of N-(hydroxyalkyl)pyrazoles and borane formed boric ester complex, in which the remaining borane was stabilized by the adjacent nitrogen of thr pyrazole ring. The borane complex derived from the chiral pyrazoles such as 3-phenyl-l-menthopyrazole reduced p-methylacetophenone (21) enantioselectively. When (2'S)-2-(2'-phenyl-2'-hydroxyethyl)-3-phenyl-l-menthopyrazole ((2'S)-10b) was used, 21 was reduced into (S)-p-methylphenyl-1-ethanol (22) in moderate chemical and optical yields. Due to the inconvenience of the preparation and the lower optical yield, the use of N-(α-hydroxyalkyl)pyrazoles was unpromising for the enantioselective reduction of ketones by borane.
Unusual Chelating Properties of the Ligand 1,8-Bis(3,5-dimethyl-1-pyrazolyl)-3,6-dithiaoctane (bddo). Crystal Structures of Ni(bddo)(NCS)2, Zn(bddo)(NCS)2 and Cd2(bddo)(NCS)4
Haanstra, Willem G.,Driessen, Willem L.,Reedijk, Jan,Turpeinen, Urho,Haemaelaeinen, Reijo
, p. 2308 - 2314 (2007/10/02)
The synthesis and characterization of the ligand 1,8-bis(3,5-dimethyl-1-pyrazolyl)-3,6-dithiaoctane (bddo) and its co-ordination compounds with zinc, cobalt, nickel, and cadmium thiocyanate are described.The general formula is M(bddo)(NCS)2 with M = Ni, C
ALKYLATION OF AZOLES USING beta -FUNCTIONAL ALKYL HALIDES UNDER CONDITIONS OF PHASE TRANSFER CATALYSIS.
Asratyan,Attaryan,Pogosyan,Eliazyan,Darbinyan,Matsoyan
, p. 1202 - 1206 (2007/10/02)
The objective of this study was to develop a convenient synthetic method for direct N-alkylation of pyrazole (I), 3(5)-methylpyrazole (II), 3,5-dimethylpyrazole (III), 1,2,4-triazole (IV), and tetrazole (V) using beta -functional alkyl halides under conditions of two-phase catalysis and with high product yields. This investigation was stimulated by the fact that the desired reaction products are intermediates in the synthesis of an important class of compounds, vinylazole, as well as of various pharmaceutical agents. It is found that depending on the acidity of the azole, alkylation with dichloroethane can be accompanied by beta -elimination. The effect of solvent on the course of alkylation reactions using dichloroethane has also been studied, and revealed that the reactions occur via the intermediacy of ion pairs rather than free anions.
