100631-80-9Relevant academic research and scientific papers
Palladium(0)-catalyzed, copper(I)-mediated coupling of boronic acids with cyclic thioamides. Selective carbon-carbon bond formation for the functionalization of heterocycles
Prokopcova, Hana,Kappe, C. Oliver
, p. 4440 - 4448 (2007)
(Chemical Equation Presented) The palladium-catalyzed cross-coupling of cyclic thioamides with arylboronic acids in the presence of stoichiometric amounts of a copper(I) cofactor is described. The desulfitative carbon-carbon cross-coupling protocol is performed under neutral conditions and can be applied to a range of heterocyclic structures with embedded thioamide fragments. Successful carbon-carbon cross-coupling is independent of the ring size, aromaticity/nonaromaticity, the presence of additional heteroatoms, or other functional groups in the starting thioamide structure. Employing controlled microwave irradiation at 100°C, most cross-couplings can be completed within 2 h and proceed in high yields. An advantage of using thioamides as starting materials is die fact that the system can be tuned to an alternative carbon-sulfur cross-coupling pathway by changing to stoichiometric copper(II) under oxidative conditions. Both types of thioamide cross-couplings are orthogonal to the traditional base-catalyzed Suzuki-Miyaura cross-coupling of aryl halides with boronic acids.
A domino desulfurative coupling-acylation-hydration-Michael addition process for the synthesis of polysubstituted tetrahydro-4H-pyrido[1,2-a]pyrimidines
Yan, Zhong-Fei,Quan, Zheng-Jun,Da, Yu-Xia,Zhang, Zhang,Wang, Xi-Cun
, p. 13555 - 13558 (2014)
A novel method for the synthesis of the polysubstituted tetrahydro-4H-pyrido[1,2-a]pyrimidines through a domino desulfurative coupling-acylation-hydration and Michael addition sequence was established. This journal is
Investigating the existence of nonthermal/specific microwave effects using silicon carbide heating elements as power modulators
Razzaq, Tahseen,Kremsner, Jennifer M.,Kappe, C. Oliver
, p. 6321 - 6329 (2008)
(Chemical Equation Presented) The use of passive heating elements made out of chemically inert sintered silicon carbide (SiC) allows microwave transparent or poorly absorbing reaction mixtures to be heated under microwave conditions. The cylindrical heating inserts efficiently absorb microwave energy and subsequently transfer the generated thermal energy via conduction phenomena to the reaction mixture. In the case of low to medium microwave absorbing reaction mixtures, the addition of SiC heating elements results in significant reductions (30-70%) in the required microwave power as compared to experiments performed without heating element at the same temperature. The method has been used to probe the influence of microwave power (electromagnetic field strength) on chemical reactions. Six diverse types of chemical transformations were performed in the presence or absence of a SiC heating element at the same reaction temperature but at different microwave power levels. In all six cases, the measured conversions/yields were similar regardless of whether a heating element was used or not. The applied microwave power had no influence on the reaction rate, and only the attained temperature governed the outcome of a specific chemical process under microwave conditions.
Wool-anchored Pd(OAc)2 complex: A highly active and reusable catalyst for desulfurative coupling reactions
Yang, Quanlu,Quan, Zhengjun,Du, Baoxin,Wu, Shang,Li, Peidong,Sun, Yanxia,Lei, Ziqiang,Wang, Xicun
, p. 4522 - 4531 (2015/09/01)
A biomacromolecule-anchored palladium complex, wool-Pd(OAc)2, was prepared and characterized by IR, XPS, SEM and ICP. The new complex was used as a catalyst for the Liebeskind-Srogl desulfurative coupling reactions of pyrimidin-yl thioether derivatives with terminal alkynes and aryl boronic acids. Products were isolated in moderate to excellent yields. When 2-(phenylthio)-1,4-dihydropyrimidine derivatives were reacted with terminal alkynes and carboxyl acids, a domino reaction process was revealed. In these reactions, this novel and efficient catalyst was capable of being reused for at least nine rounds, with durable performance and wide substrate tolerance.
Optimized Liebeskind-Srogl coupling reaction between dihydropyrimidines and tributyltin compounds
Sun, Qi,Suzenet, Franck,Guillaumet, Gérald
supporting information; experimental part, p. 2694 - 2698 (2012/07/17)
We developed an optimized Liebeskind-Srogl reaction in order to synthesize potentially biologically active 2-aryl-1,4-dihydropyrimidines. The pallado-catalyzed cross-coupling reaction between dihydropyrimidines and tributyltin derivatives appears particul
Tunable carbon-carbon and carbon-sulfur cross-coupling of boronic acids with 3,4-dihydropyrimidine-2-thiones
Lengar, Alenka,Kappe, C. Oliver
, p. 771 - 774 (2007/10/03)
Direct microwave-assisted Pd(0)-catalyzed/Cu(I)-mediated carbon-carbon cross-coupling of 3,4-dihydropyrimidine-2-thiones and boronic acids under Liebeskind-Srogl conditions leads to 2-aryl-1,4-dihydropyrimidines in moderate to high yield. In contrast, Cu(
Studies on cerebral protective agents. I. Novel 4-arylpyrimidine derivatives with anti-anoxic and anti-lipid peroxidation activities
Kuno,Sugiyama,Katsuta,Kamitani,Takasugi
, p. 1452 - 1461 (2007/10/02)
Novel 4-arylpyrimidine derivatives were synthesized by the oxidation of 4-aryl-1,4-dihydropyrimidines, and their effects on anti-anoxic (AA) activity in mice and anti-lipid peroxidation (ALP) activity in rat brain mitochondria were investigated. Among these compounds, ethyl 6-methyl-2-phenyl-4-(4-pyridyl)-5-pyrimidinecarboxylate (4b) has AA activity (10mg/kg, i.p.) and ethyl 6-methyl-4-(3-nitrophenyl)-2-phenyl-5-pyrimidinecarboxylate (4f) has ALP activity (73% inhibition at 10-5 g/ml). The latter compound (100mg/kg, i.p.) was also effective on arachidonate-induced cerebral edema in rats with comparable potency to that of vitamin E.
