This product is a nationally controlled contraband or patented product, and the Lookchem platform doesn't provide relevant sales information.
23022-83-5Relevant articles and documents
Green synthesis method of bromoaromatic amine and alpha-bromoaromatic ketone
-
Paragraph 0026-0029, (2017/07/21)
The invention discloses a green synthesis method of bromoaromatic amine and alpha-bromoaromatic ketone. The synthesis method comprises: adopting hydrobromic acid as a brominating agent, adopting 2-methylpyridine nitrate as a catalyst, and adopting molecular oxygen as an oxidizing agent, brominating an aromatic compound with a structure shown in formula (1) or aromatic ketone with a structure shown in formula (2) or (3), and preparing corresponding bromoaromatic amine or alpha-bromoaromatic ketone. The synthesis method is wide in substrate application reaction, high in atom utilization rate, capable of avoiding the application of the transitional metal element and volatile organic solvent and has the characteristics of economical efficiency and environmental protection. (Shown in the description).
Simple Method for sp2-sp3 and sp3-sp3 Carbon-Carbon Bond Activation in 2-Substituted 1,3-Diketones
Aoyama, Tadashi,Hayakawa, Mamiko,Kubota, Sho,Ogawa, Sumire,Nakajima, Erika,Mitsuyama, Emi,Iwabuchi, Taku,Kaneko, Haruki,Obara, Rina,Takido, Toshio,Kodomari, Mitsuo,Ouchi, Akihiko
supporting information, p. 2945 - 2956 (2015/09/28)
Simple and efficient methods were developed for sp2-sp3 and sp3-sp3 C-C bond-activation reactions of 2-substituted 1,3-diketones. 3-Substituted 3-bromopentane-2,4-diones were deacylated in the presence of an aromatic compound and a silica gel supported Bronsted acid containing sulfonic groups. The carbocation formed by cleavage of the sp3-sp3 C-C bond of the dione alkylated the aromatic compound.
A scalable procedure for light-induced benzylic brominations in continuous flow
Cantillo, David,De Frutos, Oscar,Rincon, Juan A.,Mateos, Carlos,Oliver Kappe
supporting information, p. 223 - 229 (2014/01/17)
A continuous-flow protocol for the bromination of benzylic compounds with N-bromosuccinimide (NBS) is presented. The radical reactions were activated with a readily available household compact fluorescent lamp (CFL) using a simple flow reactor design based on transparent fluorinated ethylene polymer (FEP) tubing. All of the reactions were carried out using acetonitrile as the solvent, thus avoiding hazardous chlorinated solvents such as CCl4. For each substrate, only 1.05 equiv of NBS was necessary to fully transform the benzylic starting material into the corresponding bromide. The general character of the procedure was demonstrated by brominating a diverse set of 19 substrates containing different functional groups. Good to excellent isolated yields were obtained in all cases. The novel flow protocol can be readily scaled to multigram quantities by operating the reactor for longer time periods (throughput 30 mmol h-1), which is not easily possible in batch photochemical reactors. The bromination protocol can also be performed with equal efficiency in a larger flow reactor utilizing a more powerful lamp. For the bromination of phenylacetone as a model, a productivity of 180 mmol h -1 for the desired bromide was achieved.
Comparison of the photochemistry of 3-methyl-2-phenyl-2h-azirine and 2-methyl-3-phenyl-2h-azirine
Zhang, Xiaoming,Sarkar, Sujan K.,Weragoda, Geethika K.,Rajam, Sridhar,Ault, Bruce S.,Gudmundsdottir, Anna D.
, p. 653 - 663 (2014/04/03)
Photolysis of 3-methyl-2-phenyl-2H-azirine (1a) in argon-saturated acetonitrile does not yield any new products, whereas photolysis in oxygen-saturated acetonitrile yields benzaldehyde (2) by interception of vinylnitrene 5 with oxygen. Similarly, photolysis of 1a in the presence of bromoform allows the trapping of vinylnitrene 5, leading to the formation of 1-bromo-1-phenylpropan-2-one (4). Laser flash photolysis of 1a in argon-saturated acetonitrile (? = 308 nm) results in a transient absorption with ?max at 440 nm due to the formation of triplet vinylnitrene 5. Likewise, irradiation of 1a in cryogenic argon matrixes through a Pyrex filter results in the formation of ketene imine 11, presumably through vinylnitrene 5. In contrast, photolysis of 2- methyl-3-phenyl-2H-azirine (1b) in acetonitrile yields heterocycles 6 and 7. Laser flash photolysis of 1b in acetonitrile shows a transient absorption with a maximum at 320 nm due to the formation of ylide 8, which has a lifetime on the order of several milliseconds. Similarly, photolysis of 1b in cryogenic argon matrixes results in ylide 8. Density functional theory calculations were performed to support the proposed mechanism for the photoreactivity of 1a and 1b and to aid in the characterization of the intermediates formed upon irradiation.
Silica sulfuric acid-promoted deacylation of α-bromo-β-diketones
Aoyama, Tadashi,Kubota, Sho,Takido, Toshio,Kodomari, Mitsuo
supporting information; experimental part, p. 484 - 485 (2011/06/25)
Novel deacylation of α-bromo-β-diketones using silica sulfuric acid (SSA) has been developed. Deacylation of 3- bromopentane-2,4-diones and 2-bromobutane-1,3-diones were carried out in the presence of SSA in dichloroethane under mild conditions to obtain the corresponding α-bromo ketones in good to excellent yields. SSA also promoted the FriedelCrafts type alkylation of benzene with 3-(sec-alkyl)-2,4-pentanediones to give the corresponding triarylmethanes in high yields in benzene.
Mild and efficient method for-thiocyanation of ketones and-dicarbonyl compounds using bromodimethylsulfonium bromide-ammonium thiocyanate
Bhalerao, Dinesh S.,Akamanchi, Krishnacharya G.
experimental part, p. 799 - 807 (2010/05/17)
An efficient and convenient method for-thiocyanation of ketones and-dicarbonyl compounds has been developed using a reagent combination of bromodimethylsulfonium bromide (BDMS) and ammonium thiocyanate in acetonitrile. The developed method is mild and gave good yield of the products at room temperature.
Azole derivatives as histamine H3 receptor antagonists, Part I: Thiazol-2-yl ethers
Walter,Von Coburg,Isensee,Sander,Ligneau,Camelin,Schwartz,Stark
supporting information; experimental part, p. 5879 - 5882 (2010/11/18)
Most human histamine H3 receptor (hH3R) antagonists follow a general structural blueprint, containing a basic moiety linked by a spacer to a substituted core element. In this investigation the acceptance of thiazol-2-yl ether moieties in the core region is proved with some ether derivatives showing hH3R binding affinities in the nanomolar concentration range. A diversity of structural motifs is used as substituents to enhance the in vitro hH3R binding affinity.
Theoretical and experimental studies on stability of the C-ON bond in new ketone functionalized N-alkoxyamines
Megiel, Elzbieta,Kaim, Andrzej,Cyranski, Michal Ksawery
experimental part, p. 1146 - 1154 (2011/09/20)
Three new ketone functionalized N-alkoxyamines derived from 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) were prepared: N-(1-phenylpropyloxy) -2,2,6,6-tetramethylpiperidin-4-one, 1-phenyl-1-(2,2,6,6- tetramethylpiperidinoxy)propanone, 1-phenyl-1-(4-oxo-2,2,6,6- tetramethylpiperidinoxy)propanone. The rate constants of C-ON bonds homolysis in the synthesized alkoxyamines were determined over a range of temperatures via nitroxide-exchange experiments using HPLC to monitor the concentration. The Arrhenius parameters of homolysis for the investigated alkoxyamines were determined (lnA, Ea). Homolytic bond dissociation energies (BDE) of the C-ON bond in the synthesized compounds were determined from quantum-mechanical calculations at the B3-LYP/6-31G(d) and BMK/6-311+G(3df,2p) levels. Ketone functionalization of the alkyl fragment of alkoxyamine in β position dramatically increases the rate constant of homolysis (by a factor of ca. 500 at the temperature of 363 K) suggesting that the new ketone functionalized N-alkoxyamines should be effective as C-radical precursor and unimolecular initiators in NMRP at lower temperatures than the alkoxyamines applied earlier. The analyses of natural bond, frontal orbitals and spin distribution indicated that the decrease in the strength of C-ON bonds in ketone fuctionalized alkoxyamines in the alkyl fragment predominantly originates from a substantially smaller HOMO-LUMO gap and more delocalized spin density in leaving alkyl radicals as compared with unfunctionalized alkoxyamines. Copyright
A convenient one-pot synthesis of thiazol-2-imines: application in the construction of pifithrin analogues
Murru, Siva,Singh,Kavala, Veerababurao,Patel, Bhisma K.
, p. 1931 - 1942 (2008/09/17)
For the first time a reaction intermediate has been isolated giving further insight into the mechanism of thiazol-2-imine formation. The first step of the reaction requires a basic medium, while the second step is an acid mediated E1 elimination reaction. An efficient one-pot synthesis of substituted thiazol-2-imines have been achieved by the condensation of carbonyl compounds with thioureas and 1,3-disubstituted thioureas using 1,1′-(ethane-1,2-diyl)dipyridinium bistribromide (EDPBT). Unsymmetrical 1,3-disubstituted thioureas give regioselective products with symmetrical ketones, which are mainly governed by the pKas of NH protons of thiourea, whereas symmetrical 1,3-disubstituted thioureas give regioselective products with symmetrical carbonyl compounds owing to the regioselective bromination of ketones. The methodology is extended to access novel neurodegenerative drug candidate pifithrin-α analogues in good yields in shorter reaction time. This method is simple, versatile and is applicable for different 1,3-disubstituted thioureas as well as a range of carbonyl compounds.