104-46-1Relevant articles and documents
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Moureu,Chauvet
, p. 412 (1897)
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Didecyldimethylammonium bromide (DDAB): a universal, robust, and highly potent phase-transfer catalyst for diverse organic transformations
Chidambaram, Mandan,Sonavane, Sachin U.,de la Zerda, Jaima,Sasson, Yoel
, p. 7696 - 7701 (2007)
Didecyldimethylammonium bromide (DDAB) has been scrutinized in comparison with traditional phase-transfer catalysts in variety of liquid-liquid reactions. It was found to be an exceptionally comprehensive, durable, and highly efficient phase-transfer catalyst (PTC) in a number of representative organic transformations such as C- and N-alkylations, isomerization, esterification, elimination, cyanation, bromination, and oxidation under very mild conditions of temperature and mixing. It was confirmed that DDAB is an exceedingly accessible and concurrently a highly liphophilic phase-transfer catalyst. This unprecedented characteristic renders DDAB to be a multipurpose catalyst that functions effectively both in mass transfer controlled and chemically controlled phase-transfer reactions.
Diastereomer-differentiating photochemistry of β-arylbutyrophenones: Yang cyclization versus type II elimination
Singhal, Nidhi,Koner, Apurba L.,Mal, Prasenjit,Venugopalan, Paloth,Nau, Werner M.,Moorthy, Jarugu Narasimha
, p. 14375 - 14382 (2005)
The diastereomers of ketones 2 and 3 are shown to exhibit distinct photochemical reactivities due to conformational preferences; while the anti isomers of 2 and 3 undergo efficient Yang cyclization in 75-90% yields with a remarkable diastereoselectivity (> 90%), the syn isomers predominantly undergo Norrish Type II elimination. The differences in the product profiles of the diastereomers are consistent with a mechanistic picture involving the formation of precursor diastereomeric triplet 1,4-biradicals in which the substituents at α and β-positions stabilize the cisoid (cyclization) or transoid (elimination) geometry. The fact that such a diastereomeric relationship does indeed ensue at the triplet-excited-state itself is demonstrated via the nanosecond laser-flash photolysis of model ketones 1. The diastereomeric discrimination in the product profiles observed for ketones 2 and 3 as well as in the triplet lifetimes observed for ketones 1 can both be mechanistically traced back to different conformational preferences of the ground-state diastereomeric ketones and the intermediary 1,4-biradicals. Additionally, it emerges from the present study that the syn and anti diastereomers of ketones 2 and 3 represent two extremes of a broad range of widely examined butyrophenones, which lead to varying degrees of Yang photocyclization depending on the alkyl substitution pattern.
Synthesis, characterization and in vitro biological evaluation of [Ru(η6-arene)(N,N)Cl]PF6 compounds using the natural products arenes methylisoeugenol and anethole
Delgado, Ricardo A.,Galdámez, Antonio,Villena, Joan,Reveco, Patricio G.,Thomet, Franz A.
, p. 131 - 137 (2015)
Abstract Five new organometallic Ru(II) compounds (VI-X) with the general formula [Ru(η6-arene)(N,N)Cl]PF6, where arene-N,N correspond to methylisoeugenol-bipyridine (VI); anethole-bipyridine (VII); methylisoeugenol-ethylenediamine (VIII); anethole-ethylenediamine (IX) and methylisoeugenol-1,2-diaminobenzene (X), have been synthesized, fully characterized and biologically evaluated in vitro. The reaction conditions based on the reduction of [Ru(1,5-COD)Cl2]n in situ with methyleugenol and estragole, which are natural ligands, induced an alkene isomerization on the allylic substituent of coordinated arenes. The Ru(II)-arene bond formation and isomerization of the CC bond on the allyl substituent was confirmed using 1H NMR spectroscopy; this result was validated for compound VIII by X-ray diffraction. An XRD analysis revealed the presence of both enantiomers of the complex in the single-crystal. Compounds IX and X exhibited a better cytotoxic activity in vitro than carboplatin, which is a commercial drug, against three human tumor cell lines (MCF-7, PC-3 and HT-29).
Phospholes as efficient ancillaries for the rhodium-catalyzed hydroformylation and hydroaminomethylation of estragole
Oliveira, Kelley C.B.,Carvalho, Sabrina N.,Duarte, Matheus F.,Gusevskaya, Elena V.,Dos Santos, Eduardo N.,Karroumi, Jamal El,Gouygou, Maryse,Urrutigo?ty, Martine
, p. 10 - 16 (2015)
The hydroaminomethylation (HAM) of estragole, a bio-renewable starting material, with di-n-butylamine was studied for the first time resulting in three novel amines. The process consists of the alkene hydroformylation followed by the in situ reductive amination of primarily formed aldehydes. In order to control chemo- and regioselectivities, three classes of phosphorus(III) compounds were employed as ancillaries for rhodium(I) catalysts: phosphine, phosphites and phospholes. Phosphole-promoted systems have showed the best overall performance, being more selective in the hydrofomylation step than non-promoted or phosphite-promoted systems, as well as more efficient in the reductive amination step than the standard triphenylphosphine based system. It has been found that both the double bond isomerization (a concurrent reaction) and the enamine hydrogenation (the last step in the HAM process) are favored by less electron-donating ligands, with phospholes presenting an excellent compromise to ensure high chemoselectivity and reasonably fast formation of target amines.
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Bohrmann,Younken Jr.
, p. 1415,1416 (1968)
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Isomerization during olefin metathesis: An assessment of potential catalyst culprits
Higman, Carolyn S.,Plais, Lucie,Fogg, Deryn E.
, p. 3548 - 3551 (2013)
Two ruthenium hydride complexes commonly proposed as agents of unintended isomerization during olefin metathesis are examined for their activity in isomerization of estragole, a representative allylbenzene. Neither proves kinetically competent to account for the levels of isomerization observed during cross-metathesis of estragole by the second-generation Grubbs catalyst. A structure-activity analysis of selected ruthenium hydride complexes indicates that higher isomerization activity correlates with a more electrophilic metal center. It wasn't me: Two Ru hydrides thought to trigger double-bond migration during olefin metathesis are examined for their isomerization activity. Neither can account for the high levels of undesired isomerization seen during self-metathesis of estragole, a model allylbenzene substrate. Higher activity is found to correlate with a less electron-rich Ru center. Copyright
Nickel-catalyzed reductive deoxygenation of diverse C-O bond-bearing functional groups
Cook, Adam,MacLean, Haydn,St. Onge, Piers,Newman, Stephen G.
, p. 13337 - 13347 (2021/11/20)
We report a catalytic method for the direct deoxygenation of various C-O bond-containing functional groups. Using a Ni(II) pre-catalyst and silane reducing agent, alcohols, epoxides, and ethers are reduced to the corresponding alkane. Unsaturated species including aldehydes and ketones are also deoxygenated via initial formation of an intermediate silylated alcohol. The reaction is chemoselective for C(sp3)-O bonds, leaving amines, anilines, aryl ethers, alkenes, and nitrogen-containing heterocycles untouched. Applications toward catalytic deuteration, benzyl ether deprotection, and the valorization of biomass-derived feedstocks demonstrate some of the practical aspects of this methodology.
Spicing up olefin cross metathesis with the renewables estragole and methyl sorbate
Ferreira, Leonildo A.,Silva, Josiane T.,Alves, Raissa G.,Oliveira, Kelley C.B.,dos Santos, Eduardo N.
, (2021/05/03)
Diene moieties conjugated to a carbonyl group are ubiquitous in nature and are present in compounds with relevant biological properties. Herein we investigate the cross metathesis (CM) of the renewable cross partners estragole and methyl sorbate (MeSo) to produce methyl 6-(4-methoxyphenyl)hexa-2,4-dienoate. By the judicious choice of the ruthenium-based metathesis catalysts, as well as the reaction conditions, it was possible to obtain good conversion and selectivity for the desired product in catalyst loadings as low as 50 ppm (0.005 mol%), with a minimal amount of solvent.
