36441-32-4Relevant articles and documents
Experimental and Computational Studies on the Ruthenium-Catalyzed Dehydrative C-H Coupling of Phenols with Aldehydes for the Synthesis of 2-Alkylphenol, Benzofuran, and Xanthene Derivatives
Baik, Mu-Hyun,Pannilawithana, Nuwan,Pudasaini, Bimal,Yi, Chae S.
supporting information, p. 13428 - 13440 (2021/09/07)
The cationic Ru-H complex [(C6H6)(PCy3)(CO)RuH]+BF4- (1) was found to be an effective catalyst for the dehydrative C-H coupling reaction of phenols and aldehydes to form 2-alkylphenol products. The coupling reaction of phenols with branched aldehydes selectively formed 1,1-disubstituted benzofurans, while the coupling reaction with salicylaldehydes yielded xanthene derivatives. A normal deuterium isotope effect was observed from the coupling reaction of 3-methoxyphenol with benzaldehyde and 2-propanol/2-propanol-d8 (kH/kD = 2.3 ± 0.3). The carbon isotope effect was observed on the benzylic carbon of the alkylation product from the coupling reaction of 3-methoxyphenol with 4-methoxybenzaldehyde (C(3) 1.021(3)) and on both benzylic and ortho-arene carbons from the coupling reaction with 4-trifluorobenzaldehdye (C(2) 1.017(3), C(3) 1.011(2)). The Hammett plot from the coupling reaction of 3-methoxyphenol with para-substituted benzaldehydes p-X-C6H4CHO (X = OMe, Me, H, F, Cl, CF3) displayed a V-shaped linear slope. Catalytically relevant Ru-H complexes were observed by NMR from a stoichiometric reaction mixture of 1, 3-methoxyphenol, benzaldehyde, and 2-propanol in CD2Cl2. The DFT calculations provided a detailed catalysis mechanism featuring an electrophilic aromatic substitution of the aldehyde followed by the hydrogenolysis of the hydroxy group. The calculations also revealed a mechanistic rationale for the strong electronic effect of the benzaldehdye substrates p-X-C6H4CHO (X = OMe, CF3) in controlling the turnover-limiting step. The catalytic C-H coupling method provides an efficient synthetic protocol for 2-alkylphenols, 1,1-disubstituted benzofurans, and xanthene derivatives without employing any reactive reagents or forming wasteful byproducts.
Synthesis and antiproliferative activity of cyclic arylidene ketones: a direct comparison of monobenzylidene and dibenzylidene derivatives
Huber, Imre,Zupk, Istvn,Kovcs, Ida J.,Minorics, Renta,Gulys-Fekete, Gergely,Masz, Gbor,Perjsi, Pl
, p. 973 - 981 (2015/02/19)
Abstract To give further insight into the influence of the structural modifications of enones and dienones on their antiproliferative properties, 25 derivatives of enones: (E)-2-benzylidene-1-cyclohexanones, (E)-2-benzylidene-1-tetralones, (E)-2-benzylidene-1-indanone, and dienones: (E,E)-2,5- or 2,6-dibenzylidene-1-cyclanones, (E,E)-3,5-dibenzylidene-4-piperidones were synthesized using a newly developed "one-pot" synthetic method. Due to the fact that all of them have the same aryl substituents (phenyl or 4-chlorophenyl) in the arylidene moiety, it is possible to compare the relevant contribution of the single-point structural modifications (type of ring or N-substitution) on their potency on the basis of their IC 50 values. Their antiproliferative activity was evaluated against the following four human adherent cancer cell lines: HeLa, A431, A2780, and MCF7. The cytotoxicity screen has revealed that the dibenzylidene dienones in general dominate the monobenzylidene enones in this respect. The nitrogen-containing heterocyclic dienones at the same time displayed higher inhibitory properties toward these human carcinoma cell lines compared with their homocyclic dienone analogs. One of the eight newly prepared 4-piperidone derivatives, N-(γ-oxobutyl)-(E,E)-3,5-bis(p-chlorobenzylidene)-4-piperidone is as potent a cell growth inhibitor (IC 50 of 0.438-1.409 μM) as the N-methyl-(E,E)-3,5-bis(p-chlorobenzylidene)-4-piperidone (IC 50 of 0.447-1.048 μM), one of the most active among the previously described compounds in this series. Catalytic hydrogen-transfer isomerization of compounds with two exocyclic benzylidene double bonds to derivatives with endocyclic double bonds results in the complete loss of antiproliferative activity. The structural modifications and 50 % inhibitory concentration (IC 50) values resulted in correlations which can promote the design of more potent derivatives of the 4-piperidone dienones.
Novel chromogenic aminopeptidase substrates for the detection and identification of clinically important microorganisms
Cellier, Marie,James, Arthur L.,Orenga, Sylvain,Perry, John D.,Rasul, Ari K.,Robinson, Shaun N.,Stanforth, Stephen P.
, p. 5249 - 5269 (2014/12/11)
A series of amino acid derivatives 8-10, 42 and 43 have been prepared as chromogenic enzyme substrates in order to detect aminopeptidase activity in clinically important Gram-negative and Gram-positive bacteria. Enzymatic hydrolysis liberates the amino ac
Microwave-Assisted solid-liquid phase alkylation of naphthols
Balint, Erika,Kovacs, Orsolya,Drahos, Laszlo,Keglevich, Gyoergy
, p. 330 - 336 (2013/07/26)
The microwave promoted alkylation of 1- and 2-naphthols with benzyl, butyl, ethyl and isopropyl halides in the presence of an alkali carbonate may result in O- and C-Alkylated products. The alkylations were O-selective in the presence of K2CO3 in acetonitrile as the solvent and in the absence of phase transfer catalyst. The alkylations utilizing butyl and ethyl halides were also O-selective in solventless accomplishment and in the presence of triethylbenzylammonium chloride.
Photo-Fries reaction in water made selective with a capsule
Kaanumalle, Lakshmi S.,Gibb, Corinne L. D.,Gibb, Bruce C.,Ramamurthy
, p. 236 - 238 (2008/03/14)
The water soluble capsule formed by a deep cavity cavitand with eight carboxylic acid groups controls product distribution during photo-Fries rearrangement of naphthyl esters in water by restricting the mobility of primary singlet radical pair. The Royal Society of Chemistry.
Mediation of photochemical reactions of 1-naphthyl phenylacylates by polyolefin films. A 'radical clock' to measure rates of radical-pair cage recombinations in 'viscous space'
Gu, Weiqiang,Weiss, Richard G.
, p. 6913 - 6925 (2007/10/03)
The fates of phenylacyl/1-naphthoxy singlet radical pairs generated upon irradiation of 1-naphthyl phenylacetate (1a) and 1-naphthyl 2-phenylpropanoate (1b) in three unstretched and stretched polyethylene films and isotactic and syndiotactic polypropylene films have been investigated. From dynamic fluorescence measurements the primary locus of reactions by 1 is within amorphous regions of the films. The reaction cages afforded by these media inhibit escape of the radical pairs and mediate their reorientational motions leading to photo-Fries and related products. In essence, the cages act as stiff-walled templates. In addition, a method is described to measure the rate constants for the singlet radical pairs. Thus, the rate constants (leading to the keto precursors) of the 2-phenylacyl-1-naphthols from the radical pairs of 1 (> 108 s-1) are >6 times the rate constants for the 4-isomers. Film stretching increases this selectivity but there is no obvious correlation between the rate of the in-cage radical pair recombinations and macroscopic polymer, properties such as degree of crystallinity and frequency of branched chains. By contrast, formation of (the keto precursors of) 2-benzylic-1-naphthols (from in-cage recombinations after phenylacyl decarbonylation) is slower than for the 4-benzyl-1-naphthols. (C) 2000 Elsevier Science Ltd.
2-Substituted-1-naphthols as potent 5-lipoxygenase inhibitors with topical antiinflammatory activity
Batt,Maynard,Petraitis,Shaw,Galbraith,Harris
, p. 360 - 370 (2007/10/02)
The synthesis, biological evaluation, and structure-activity relationships of a series of 1-naphthols bearing carbon substituents at the 2-position are described. These compounds are potent inhibitors of the 5-lipoxygenase from RBL-1 cells and also inhibi
