1746-13-0Relevant articles and documents
Preparation and Properties of Ethylpalladium Thiolate Complexes. Reaction with Organic Halides leading to C-S Bond Formation; Crystal Structure of trans-
Osakada, Kohtaro,Ozawa, Youichi,Yamamoto, Akio
, p. 759 - 764 (1991)
The complexes trans- (R=Ph, 1; or C6H4Me-p, 2) and trans- 3 have been prepared by reactions of trans- or trans- with allyl aryl sulphides.Complex 1 reacts with various organic halides such as allyl chloride, benzyl bromide and methyl iodide to give allyl phenyl sulphide and methyl phenyl sulphide, respectively; trans- (X=Cl, 4; B3, 5; or I, 6) were isolated from the reaction mixtures.The complexe trans- also reacts with allyl chloride to give allyl phenyl ether together with complex 4.The structure of complex 5 has been determined by X-ray crystallography: orthorhombic, space group Pbca with a=12.306(3), b=20.078(5), c=11.753(2) Angstroem, Z=8, R=0.036 and R'=0.042.It has a square-planar co-ordination around the palladium centre.The reaction of allyl chloride with complex 1 in toluene obeys first-order kinetics in the concentrations of both allyl chloride and 1.
Nucleophilic Fluorination with KF Catalyzed by 18-Crown-6 and Bulky Diols: A Theoretical and Experimental Study
Silva, Samuel L.,Valle, Marcelo S.,Pliego, Josefredo R.
, p. 15457 - 15465 (2020)
The activation of potassium fluoride for nucleophilic fluorination of alkyl halides is an important challenge because of the high lattice energy of this salt and its low solubility in many polar aprotic solvents. Crown ethers have been used for increasing the solubilization of KF during several decades. Nevertheless, these macrocycles are not enough to produce a high reaction rate. In this work, theoretical methods were used for designing a synergic combination of bulky diols with crown ethers able to accelerate this kind of reaction. The calculations have predicted that the bulky diol 1,4-Bis(2-hydroxy-2-propyl)benzene, which has distant hydroxyl groups, is able to catalyze nucleophilic fluorination in combination with 18-crown-6 via two hydrogen bonds to the SN2 transition state. Experimental studies following the theoretical predictions have confirmed the catalytic effect and the estimated kinetic data point out that the bulky diol at 1 mol L-1 in combination with 18-crown-6 is able to produce an 18-fold increase in the reaction rate in relation to crown ether catalysis only. The reaction produces 46% yield of fluorination after 24 h at moderate temperature of 82 °C, with minimal formation of the side elimination product. Thus, this work presents an improved method for fluorination with KF salt.
A Pd-bisphosphine complex and organic functionalities immobilized on the same SiO2 surface: Detailed characterization and its use as an efficient catalyst for allylation
Motokura, Ken,Saitoh, Koki,Noda, Hiroto,Chun, Wang-Jae,Miyaji, Akimitsu,Yamaguchi, Sho,Baba, Toshihide
, p. 5380 - 5388 (2016)
A Pd-bisphosphine complex and several organic functionalities were immobilized on the same SiO2 surface. The samples thus prepared were characterized by solid-state NMR, XPS, and XAFS. Based on the curve-fitting analysis of Pd K-edge EXAFS spectra, both the local environment of the immobilized Pd complexes and the interactions with the co-immobilized organic functions were discussed. The SiO2-supported Pd-bisphosphine complex and DABCO exhibited excellent catalytic performance for the allylation of various nucleophiles: a TON of up to 106000 was obtained. Both the catalyst activation pathway and the reaction mechanism were also discussed on the basis of the structure of the used catalyst samples.
Preparation method 3 - phenoxybromopropane or analogue thereof
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Paragraph 0024-0026, (2021/11/26)
The invention discloses a preparation method of 3 -phenoxybromopropane or an analogue thereof, wherein 3 - phenoxybromopropane and an allyl compound thereof are obtained through substitution reaction and addition reaction so as to avoid the inconvenience of using gaseous hydrogen bromide, 2nd-step addition reaction is realized by using the brominated salt and the acid in situ, and the process is simple in operation. The condition is easy to control, the atom economy is good, the aspect of environmental impact is low pollution, zero emission accords with the current green chemical synthesis direction, and the cost is economic.
Mild and efficient desulfurization of thiiranes with MoCl5/Zn system
Lee, Yeong Jin,Shin, Jeong Won,Yoo, Byung Woo
, (2021/11/10)
Desulfurization of a variety of thiiranes to alkenes occurs chemoselectively in high yields upon treatment with MoCl5/Zn system under mild conditions. The new methodology demonstrates high functional group tolerance toward chloro, bromo, fluoro, methoxy, ester, ether and keto groups.
Zinc salt-catalyzed reduction of α-aryl imino esters, diketones and phenylacetylenes with water as hydrogen source
Shen, Guoli,Liu, Haojie,Chen, Jingchao,He, Zhenxiu,Zhou, Yongyun,Wang, Lin,Luo, Yang,Su, Zhimin,Fan, Baomin
supporting information, p. 3601 - 3610 (2021/05/04)
The zinc salt-catalyzed reduction of α-aryl imino esters, diketones and phenylacetylenes with water as hydrogen source and zinc as reductant was successfully conducted. The presented method provides a low-cost, environmentally friendly and practical preparation of α-aryl amino esters, α-hydroxyketones and phenylethylenes. By using D2O as deuterium source, the corresponding products were obtained in high efficiency with excellent deuterium incorporation rate, which gives a cheap and safe tool for access to valuable deuterium-labelled compounds. This journal is
Aluminium chloride-potassium iodide-acetonitrile system: A mild reagent system for aromatic claisen rearrangement at ambient temperature
Bhattacharyya, Nayan Kamal,Dutta, Deepjyoti,Biswas, Joydeep
, (2021/06/28)
Claisen rearrangement is used as the standard methods for the generation of complex organic substance. It is one of the well-known methods for the introduction of carbon-carbon bond. We have developed a protocol using allyl aryl ether as a substrate and AlCl3-KI as a mild reagent system and acetonitrile (CH3CN) is taken as solvent at ambient temperature. The reagent system presented in this current work is found to be appropriate for Claisen rearrangement of several aromatic alcohols with excellent yields.
Metal-free Photochemical Atom Transfer Radical Addition (ATRA) of BrCCl3 to Alkenes
Nikitas, Nikolaos F.,Voutyritsa, Errika,Gkizis, Petros L.,Kokotos, Christoforos G.
supporting information, p. 96 - 101 (2021/01/04)
A simple, photochemical, and metal-free protocol for the atom transfer radical addition (ATRA) of bromotrichloromethane onto various alkenes is described. Among a range of organic molecules, phenylglyoxylic acid proved to be the most suitable photoinitiator to promote a sustainable process for the addition of bromotrichloromethane to olefins. This photochemical atom transfer radical protocol can be expanded into a wide substrate scope of aliphatic olefins bearing various functional groups, leading to the corresponding products in good to excellent yields.
Allylphenols as a new class of human 15-lipoxygenase-1 inhibitors
Alavi, Seyed Jamal,Seyedi, Seyed Mohammad,Saberi, Satar,Safdari, Hadi,Eshghi, Hossein,Sadeghian, Hamid
, p. 259 - 266 (2020/10/12)
In this study, a series of mono- and diallylphenol derivative were designed, synthesized, and evaluated as potential human 15-lipoxygenase-1 (15-hLOX-1) inhibitors. Radical scavenging potency of the synthetic allylphenol derivatives was assessed and the results were in accordance with lipoxygenase (LOX) inhibition potency. It was found that the electronic natures of allyl moiety and para substituents play the main role in radical scavenging activity and subsequently LOX inhibition potency of the synthetic inhibitors. Among the synthetic compounds, 2,6-diallyl-4-(hexyloxy)phenol (42) and 2,6-diallyl-4-aminophenol (47) showed the best results for LOX inhibition (IC50 = 0.88 and 0.80 μM, respectively).
Novel potent (dihydro)benzofuranyl piperazines as human histamine receptor ligands – Functional characterization and modeling studies on H3 and H4 receptors
Corrêa, Michelle F.,Balico-Silva, André L.,Kiss, Dóra J.,Fernandes, Gustavo A.B.,Maraschin, Jhonatan C.,Parreiras-e-Silva, Lucas T.,Varela, Marina T.,Sim?es, Sarah C.,Bouvier, Michel,Keser?, Gy?rgy M.,Costa-Neto, Claudio M.,Fernandes, Jo?o Paulo S.
, (2020/12/21)
Histamine acts through four different receptors (H1R-H4R), the H3R and H4R being the most explored in the last years as drug targets. The H3R is a potential target to treat narcolepsy, Parkinson's disease, epilepsy, schizophrenia and several other CNS-related conditions, while H4R blockade leads to anti-inflammatory and immunomodulatory effects. Our group has been exploring the dihydrobenzofuranyl-piperazines (LINS01 series) as human H3R/H4R ligands as potential drug candidates. In the present study, a set of 12 compounds were synthesized from adequate (dihydro)benzofuran synthons through simple reactions with corresponding piperazines, giving moderate to high yields. Four compounds (1b, 1f, 1g and 1h) showed high hH3R affinity (pKi > 7), compound 1h being the most potent (pKi 8.4), and compound 1f showed the best efficiency (pKi 8.2, LE 0.53, LLE 5.85). BRET-based assays monitoring Gαi activity indicated that the compounds are potent antagonists. Only one compound (2c, pKi 7.1) presented high affinity for hH4R. In contrast to what was observed for hH3R, it showed partial agonist activity. Docking experiments indicated that bulky substituents occupy a hydrophobic pocket in hH3R, while the N-allyl group forms favorable interactions with hydrophobic residues in the TM2, 3 and 7, increasing the selectivity towards hH3R. Additionally, the importance of the indole NH in the interaction with Glu5.46 from hH4R was confirmed by the modeling results, explaining the affinity and agonistic activity of compound 2c. The data reported in this work represent important findings for the rational design of future compounds for hH3R and hH4R.
