- Reactions of 3-arylpropenenitriles with arenes under superelectrophilic activation conditions: Hydroarylation of the carbon-carbon double bond followed by cyclization into 3-arylindanones
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Reactions of 3-arylpropenenitriles [ArCH[dbnd]CHCN] with arenes [Ar'H] under the superelectrophilic activation conditions with Br?nsted superacid TfOH (CF3SO3H) or strong Lewis acid AlBr3 result, first, in the formation of products of hydroarylation of the carbon-carbon double bond, 3,3-diarylpropanenitriles [Ar(Ar’)CHCH2CN]. Reactions may go further in TfOH leading to 3-arylindanones, as products of intramolecular aromatic acylation by the electrophilically activated nitrile group. Intermediate cationic species, derived at the protonation of the starting 3-arylpropenenitriles onto the carbon of C[dbnd]C bond and the nitrile nitrogen, have been studied by DFT calculation. A plausible reaction mechanism including the formation of highly reactive dications [(Ar)HC+–CH2C+ = NH] has been proposed. The obtained 3,3-diarylpropanenitriles have been transformed into pharmaceutically valuable 5-(2,2-diarylethyl)-1H-tetrazoles [Ar(Ar’)CHCH2Tetr] and 3-diarylpropylamines [Ar(Ar’)CH(CH2)2NH2] by the reactions with NaN3 and LiAlH4 correspondingly.
- Gorbunova, Yelizaveta,Zakusilo, Dmitriy N.,Boyarskaya, Irina A.,Vasilyev, Aleksander V.
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- Rh-catalyzed 1,4-addition reactions of arylboronic acids accelerated by co-immobilized tertiary amine in silica mesopores
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Mesoporous silica-supported Rh complex catalysts were prepared by simple silane-coupling, followed by complexation, and characterized by FT-IR, SEM, Rh K-edge XAFS, and elemental analysis. Local structures of the Rh complexes in each sample were almost similar to those of a nonporous silica-supported diaminorhodium complex. Co-immobilization of a tertiary amine on the same silica surface induced slight changes to the Rh complex structure in the case of the support with smaller pores. The prepared catalysts showed high activity for the 1,4-addition reaction of phenylboronic acids. Co-immobilization of the tertiary amine increased the reaction rate by more than 7-fold, with turnover number of nearly 8500. The catalytic performance achieved with this novel system is with much higher than that reported previously with a nonporous silica-supported catalyst. The mesoporous silica-supported Rh complex-tertiary amine showed a wide substrate scope, including unsaturated ketones and nitriles. This co-immobilized tertiary amine may activate phenylboronic acid to enhance its reactivity in the transmetalation step with Rh-OH species.
- Motokura, Ken,Hashiguchi, Kohei,Maeda, Kyogo,Nambo, Masayuki,Manaka, Yuichi,Chun, Wang-Jae
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- Double metal cyanides as heterogeneous Lewis acid catalysts for nitrile synthesis: Via acid-nitrile exchange reactions
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A series of transition metal-based double metal cyanides (DMCs) were studied as catalysts for the synthesis of nitriles via acid-nitrile exchange reaction. The best nitrile yields were obtained with Co3[Co(CN6)]2 DMC, which proved to be a versatile, stable, reusable and highly active catalyst, exhibiting an activity comparable to that of homogeneous Lewis acid catalysts.
- Marquez, Carlos,Corbet, Matthieu,Smolders, Simon,Marion, Philippe,De Vos, Dirk
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supporting information
p. 12984 - 12987
(2019/11/05)
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- Cinnamonitrile as a precursor of a bi-centered electrophile in reactions with arenes in triflic acid
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The reaction of cinnamonitrile [PhCH = CHCN] with arenes in the superacid TfOH at room temperature for 1 h gave two types of compounds, 3-aryl-3-phenyl propionitriles [Ar(Ph)CHCH2CN] and/or 3-phenylindanones in 28–76% yield. The formation of these two reaction products depends on the nucleophilicity of the arene. In these reactions, carbocations generated upon the protonation of cinnamonitrile in TfOH behave as bi-centered electrophiles possessing reactive centers on the C3 carbon of the double bond and on the C1 carbon of the nitrile group.
- Gorbunova, Yelizaveta,Zakusilo, Dmitriy N.,Vasilyev, Aleksander V.
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supporting information
p. 961 - 964
(2019/03/06)
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- Cooperative Palladium/Lewis Acid-Catalyzed Transfer Hydrocyanation of Alkenes and Alkynes Using 1-Methylcyclohexa-2,5-diene-1-carbonitrile
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Catalytic transfer hydrocyanation represents a clean and safe alternative to hydrocyanation processes using toxic HCN gas. Such reactions provide access to pharmaceutically important nitrile derivatives starting with alkenes and alkynes. Herein, an efficient and practical cooperative palladium/Lewis acid-catalyzed transfer hydrocyanation of alkenes and alkynes is presented using 1-methylcyclohexa-2,5-diene-1-carbonitrile as a benign and readily available HCN source. A large set of nitrile derivatives (>50 examples) are prepared from both aliphatic and aromatic alkenes with good to excellent anti-Markovnikov selectivity. A range of aliphatic alkenes engage in selective hydrocyanation to provide the corresponding nitriles. The introduced method is useful for chain walking hydrocyanation of internal alkenes to afford terminal nitriles in good regioselectivities. This protocol is also applicable to late-stage modification of bioactive molecules.
- Bhunia, Anup,Bergander, Klaus,Studer, Armido
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supporting information
p. 16353 - 16359
(2018/11/25)
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- HPLC-based kinetics assay facilitates analysis of systems with multiple reaction products and thermal enzyme denaturation
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Glucosinolates are plant secondary metabolites abundant in Brassica vegetables that are substrates for the enzyme myrosinase, a thioglucoside hydrolase. Enzyme-mediated hydrolysis of glucosinolates forms several organic products, including isothiocyanates (ITCs) that have been explored for their beneficial effects in humans. Myrosinase has been shown to be tolerant of non-natural glucosinolates, such as 2,2-diphenylethyl glucosinolate, and can facilitate their conversion to non-natural ITCs, some of which are leads for drug development. An HPLC-based method capable of analyzing this transformation for non-natural systems has been described. This current study describes (1) the Michaelis–Menten characterization of 2,2-diphenyethyl glucosinolate and (2) a parallel evaluation of this analogue and the natural analogue glucotropaeolin to evaluate effects of pH and temperature on rates of hydrolysis and product(s) formed. Methods described in this study provide the ability to simultaneously and independently analyze the kinetics of multiple reaction components. An unintended outcome of this work was the development of a modified Lambert W(x) which includes a parameter to account for the thermal denaturation of enzyme. The results of this study demonstrate that the action of Sinapis alba myrosinase on natural and non-natural glucosinolates is consistent under the explored range of experimental conditions and in relation to previous accounts.
- Klingaman, Chase A.,Wagner, Matthew J.,Brown, Justin R.,Klecker, John B.,Pauley, Ethan H.,Noldner, Colin J.,Mays, Jared R.
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- Process for the Catalytic Reversible Alkene-Nitrile Interconversion
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The present invention refers to processes for catalytic reversible alkene-nitrile interconversion through controllable HCN-free transfer hydrocyanation.
- -
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Page/Page column 14; 15
(2017/09/02)
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- Simple Copper Catalysts for the Aerobic Oxidation of Amines: Selectivity Control by the Counterion
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We describe the use of simple copper-salt catalysts in the selective aerobic oxidation of amines to nitriles or imines. These catalysts are marked by their exceptional efficiency, operate at ambient temperature and pressure, and allow the oxidation of amines without expensive ligands or additives. This study highlights the significant role counterions can play in controlling selectivity in catalytic aerobic oxidations.
- Xu, Boran,Hartigan, Elizabeth M.,Feula, Giancarlo,Huang, Zheng,Lumb, Jean-Philip,Arndtsen, Bruce A.
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supporting information
p. 15802 - 15806
(2016/12/16)
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- Deboronative cyanation of potassium alkyltrifluoroborates: Via photoredox catalysis
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A photoredox catalytic method was developed for the direct cyanation of alkyltrifluoroborates. This reaction provides a new and useful transformation of the easily available alkyltrifluoroborates. The photocatalytic reaction can tolerate a variety of functional groups with mild reaction conditions. Mechanistic investigations are consistent with the present reaction following a radical pathway.
- Dai, Jian-Jun,Zhang, Wen-Man,Shu, Yong-Jin,Sun, Yu-Yang,Xu, Jun,Feng, Yi-Si,Xu, Hua-Jian
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p. 6793 - 6796
(2016/06/01)
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- Nitrile synthesis through catalyzed cascades involving acid-nitrile exchange
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Irreversible acid-nitrile exchange reactions using both glutaronitrile and (phenylsulfonyl)acetonitrile may be catalyzed by Lewis acids. Whereas a cyclization towards imides displaces the equilibria in the reaction with dinitriles, a decarboxylation step is involved when using the (phenylsulfonyl)acetonitrile. Georg Thieme Verlag Stuttgart New York.
- Cartigny, Damien,Dos Santos, Aurelie,El Kaim, Laurent,Grimaud, Laurence,Jacquot, Roland,Marion, Philippe
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p. 1802 - 1806
(2014/07/08)
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- Method for producing compounds comprising nitrile functions
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The present invention concerns the production of compounds comprising nitrite functions and cyclic imide compounds. More specifically, the invention relates to the production of compounds comprising nitrile functions from compounds comprising carboxylic functions, advantageously of natural and renewable origin, and from methyl-2 glutaronitrile (MGN) or a mixture N of dinitriles comprising methyl-2 glutaronitrile (MGN), ethyl-2 succinonitrile (ESN) and adiponitrile (AdN).
- -
-
Paragraph 0071-0075; 0077-0078
(2014/12/09)
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- Heck reactions catalyzed by Pd(0)-PVP nanoparticles under conventional and microwave heating
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Pd(0) nanoparticles stabilized by polyvinylpyrrolidone (Pd-PVP) with a diameter of 3-6 nm in ethanol catalyzed Heck coupling of iodobenzene with different alkenes under microwave heating. Products were obtained in good yields (62-99%) and good selectivity to the E-isomers. Microwave heating proved to be superior to conventional heating, providing products in higher yields and selectivities in short times (12 min).
- Martins, Daniela De L.,Alvarez, Heiddy M.,Aguiar, Lúcia C.S.,Antunes, Octavio A.C.
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experimental part
p. 47 - 53
(2012/04/11)
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- Iridium-catalyzed α-alkylation of acetonitrile with primary and secondary alcohols
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Acetonitrile is successfully alkylated with primary and secondary alcohols in the presence of t-BuOK using [Ir(OH)- (cod)]2 as a catalyst. This method provides a very clean and atom-economical convenient direct route to substituted nitriles, which are very important raw materials in organic and industrial chemistry.
- Sawaguchi, Takuya,Obora, Yasushi
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supporting information; experimental part
p. 1055 - 1057
(2011/12/05)
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- Rhodium-grafted hydrotalcite catalyst for heterogeneous 1,4-addition reaction of organoboron reagents to electron deficient olefins
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A rhodium-grafted hydrotalcite (Rh/HT) was prepared by the treatment of a Mg-Al mixed hydroxide (hydrotalcite, HT) with an aqueous RhCl 3·nH2O solution. The formation of the Rh III species on the HT surface was confirmed by X-ray absorption fine structure spectroscopy. The Rh/HT catalyst was demonstrated to effectively promote the 1,4-addition reaction of organoboron reagents to electron-deficient olefins in both organic and aqueous solvents. The strong surface basicity of HT facilitates the formation of a Rh-OH species, which possesses high nucleophilicity, leading to an efficient transmetalation with organoboron reagents. This catalyst system is also applicable in the one-pot three-component synthesis of 2-cyano-3,3-diphenyl propionate due to the bifunctionality of the Rh/HT surface.
- Motokura, Ken,Hashimoto, Norifumi,Hara, Takayoshi,Mitsudome, Takato,Mizugaki, Tomoo,Jitsukawa, Koichiro,Kaneda, Kiyotomi
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experimental part
p. 2416 - 2422
(2011/10/13)
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- Controlled conversion of phenylacetic acids to phenylacetonitriles or benzonitriles using bis(2-methoxyethyl)aminosulfur trifluoride
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A mild, efficient, and practical method for the one-step synthesis of benzonitriles from phenylacetic acids using bis(2-methoxyethyl)aminosulfur trifluoride is described. The reaction was easily extended to the synthesis of the corresponding phenylacetonitriles by inclusion of triethylphosphine.
- Kangani, Cyrous O.,Day, Billy W.,Kelley, David E.
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p. 914 - 918
(2008/09/17)
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- Direct, facile synthesis of acyl azides and nitriles from carboxylic acids using bis(2-methoxyethyl)aminosulfur trifluoride
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A mild, efficient, and practical method for the one-step synthesis of acyl azides from carboxylic acids using bis(2-methoxyethyl)aminosulfur trifluoride is described. The reaction was easily extended to the synthesis of the corresponding nitriles by the inclusion of phosphorous reagents. The method can be applied to the synthesis of optically active nitriles in high yields, and is compatible with fluorous phosphines.
- Kangani, Cyrous O.,Day, Billy W.,Kelley, David E.
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p. 5933 - 5937
(2008/02/10)
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- Organo[2-(hydroxymethyl)phenyl]dimethylsilanes as mild and reproducible agents for rhodium-catalyzed 1,4-addition reactions
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Stable and reusable tetraorganosilicon reagents, alkenyl-, aryl-, and silyl[2-(hydroxymethyl)phenyl]-dimethylsilanes, undergo 1,4-addition reactions to α,β-unsaturated carbonyl acceptors under mild rhodium-catalysis. The reaction tolerates a diverse range of functional groups and is applicable to gram-scale synthesis. Use of a chiral diene ligand allows the achievement of the corresponding enantioselective transformations using the tetraorganosilicon reagents, providing the silicon-based approach to optically active ketones and substituted piperidones that serve as synthetic intermediates of pharmaceuticals. A rhodium alkoxide species is suggested to be responsible for a transmetalation step on the basis of the observed kinetic resolution of a racemic chiral phenylsilane in the enantioselective 1,4-addition reaction under the rhodium-chiral diene catalysis.
- Nakao, Yoshiaki,Chen, Jinshui,Imanaka, Hidekazu,Hiyama, Tamejiro,Ichikawa, Yoshitaka,Duan, Wei-Liang,Shintani, Ryo,Hayashi, Tamio
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p. 9137 - 9143
(2008/02/09)
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- Palladium(II)-catalyzed conjugate addition of arylsiloxanes in water
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Equation Presented Palladium-phosphinous acids catalyze the conjugate addition of arylsiloxanes to a wide range of α.β-unsaturated substrates in water microwave-assisted procedure is described that uses 5 mol % of POPd1 to afford /-substituted ketones, aldehydes, esters, nitriles, an nitroalkanes in 83% to 96% yield within 4 h. This method eliminates the need for stoichiometric additives and an excess of arylsiloxane, an does not require an inert atmosphere.
- Lerebours, Rachel,Wolf, Christian
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p. 2737 - 2740
(2008/02/07)
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- A rhodium-grafted hydrotalcite as a highly efficient heterogeneous catalyst for 1,4-addition of organoboron reagents to α,β-unsaturated carbonyl compounds
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Treatment of a hydrotalcite with an aqueous solution of rhodium trichloride results in a Rh-grafted hydrotalcite (Rh/HT) with monomeric Rh species on the surface, which successfully promoted 1,4-addition of organoboron reagents to α,β-unsaturated carbonyl compounds. Furthermore, this catalyst was reusable and was found to be applicable to a one-pot synthesis of 3,3-diarylnitrile.
- Fujita, Noriaki,Motokura, Ken,Mori, Kohsuke,Mizugaki, Tomoo,Ebitani, Kohki,Jitsukawa, Koichiro,Kaneda, Kiyotomi
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p. 5083 - 5087
(2007/10/03)
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- Histaprodifens: Synthesis, pharmacological in vitro evaluation, and molecular modeling of a new class of highly active and selective histamine H1-receptor agonists
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A new class of histamine analogues characterized by a 3,3-diphenylpropyl substituent at the 2-position of the imidazole nucleus has been prepared outgoing from 4,4-diphenylbutyronitrile (4b) via cyclization of the corresponding methyl imidate 5b with 2-oxo-4-phthalimido-1-butyl acetate or 2-oxo-1,4-butandiol in liquid ammonia, followed by standard reactions. The title compounds displayed partial agonism on contractile H1 receptors of the guinea-pig ileum and endothelium-denuded aorta, respectively, except 10 (histaprodifen; 2-[2-(3,3-diphenylpropyl)1H-imidazol-4-yl]ethanamine) which was a full agonist in the ileum assay. While 10 was equipotent with histamine (1), methylhistaprodifen (13) and dimethylhistaprodifen (14) exceeded the functional potency of 1 by a factor of 3-5 (13) and 2-3 (14). Compounds 10 and 13-17 relaxed precontracted rat aortic rings (intact endothelium) with relative potencies of 3.3- up to 28-fold (compared with 1), displaying partial agonism as well. Agonist effects were sensitive to blockade by the selective H1-receptor antagonist mepyramine (pA2 ? 9 (guinea-pig) and pA2 ? 8 (rat aorta)). The affinity of 10 and 13-17 for guinea-pig H1 receptors increased 20- to 100-fold compared with 1. Two lower homologues of 10 were weak partial H1-receptor agonists while two higher homologues of 10 were silent antagonists endowed with micromolar affinity for rat and guinea-pig H1 receptors. In functional selectivity experiments, 10, 13, and 14 did not stimulate H2, H3, and several other neurotransmitter receptors. They displayed only low to moderate affinity for these sites (pA2 1 receptor were studied using molecular dynamics simulations. Remarkable differences were found between the binding modes of 10, 13, and 14 and that of 1. The imidazole ring of 10, 13, and 14 was placed 'upside down' compared with 1, making the interaction of the N(π)-atom with Tyr431 possible. This new orientation was mainly caused by the space filling substitution at the 2-position of the imidazole ring and influenced the location of the protonated N(α)-atom which was positioned more between TM III and TM VI. This orientation can explain both the increased relative potency and the maximum effect of 10, 13, and 14 compared with 1. Compound 13 (methylhistaprodifen; N(α)-methyl-2-[2-(3,3-diphenylpropyl)-1H-imidazol-4- yl]ethanamine) is the most potent histamine H1-receptor agonist reported so far in the literature and may become a valuable tool for the study of physiological and pathophysiological H1-receptor-mediated effects.
- Elz, Sigurd,Kramer, Kai,Pertz, Heinz H.,Detert, Heiner,Ter Laak, Anton M.,Kühne, Ronald,Schunack, Walter
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p. 1071 - 1084
(2007/10/03)
-
- Agents for the treatment of overactive detrusor. IV. Synthesis and structure-activity relationships of cyclic analogues of terodiline
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A series of pyrrolidine derivatives were synthesized and examined for inhibitory activity on detrusor contraction in vivo. Among those compounds, 5,5-dimethyl-2-(2,2-diphenylethyl)-3-isopropylidenepyrrolidine hydrochloride (41 · HCl), 2-(2,2-di(4-fluorophenyl)ethylene)-5,5-dimethyl-3-isopropylidenepyrrol idine hydrochloride (42 · HCl), (+)5,5-dimethyl-2-(N,N-diphenylaminomethyl)-3-isopropylidenepyrrolidin e hydrochloride (+)-(43a · HCl),(-)-5,5-dimethyl-2-(N,N-diphenylaminomethyl)-3-isopropylidenepyrr olidine hydrochloride (-)-(43a · HCl), and 2-(N,N-di(4-fluorophenyl)aminomethyl)-5,5-dimethyl-3-isopropylidenepyr rolidine methanesulfonate (43b · MsOH) showed stronger inhibitory activity on detrusor contraction than terodiline.
- Take,Okumura,Tsubaki,Terai,Shiokawa
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p. 507 - 515
(2007/10/02)
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- A convenient preparation of alkyl nitriles by the Mitsunobu procedure
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A convenient preparation of alkyl nitriles from alcohols extending the use of the Mitsunobu reaction is described. Acetone cyanohydrin is the acidic component and the source of cyanide ion.
- Wilk
-
p. 2481 - 2484
(2007/10/02)
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- Photo-heterolysis and -homolysis of substituted diphenylmethyl halides, acetates, and phenyl ethers in acetonitrile: Characterization of diphenylmethyl cations and radicals generated by 248-nm laser flash photolysis
-
Para-substituted diphenylmethyl halides, acetates, and ethers RPh(R′Ph)CH-X (R, R′ = CF3 to OCH3), upon photolysis with ~250-nm light in acetonitrile solutions, undergo homolysis and heterolysis of the C-X bond to give the radicals, RPh(R′Th)CH? (abbreviated as C?), and the cations, RPh(R′Ph)CH+ (C+). Whereas the quantum yields for homolysis (0.2-0.4) are rather independent of the nature of the substituent on the benzene ring, those for heterolysis increase with increasing electron-donator strength from ≤0.07 for CF3 to 0.3 for OMe. The cation:radical ratios are also dependent on the nucleofugal properties of X. For the halides, the observed heterolysis:homolysis ratios correlate with the pKa values of the conjugate acids HX and not with the electron affinities of X?. In acetonitrile, heterolysis is much less endothermic than homolysis. Homolysis and heterolysis can also be effected indirectly by reaction with triplet acetophenone (produced by 308-nm photolysis). Unless stabilized by one or more MeO, the cations decay predominantly by reaction with acetonitrile to give nitrilium ions. However, since this reaction is reversible (shown for the benzhydryl cation), the nitrilium ion contributes only to an insignificant degree to the formation of the final (cation-derived) products, which result from reaction with trace water (main product, benzhydryl alcohol; minor, benzhydrylacetamide). The rate constants for addition of C+ to CH3CN are in the range 3.5 × 105 to 3.8 × 107 s-1 for the cations with R = R′ = Me to R = H, R′ = CF3. The rate constants for reaction of C+ with halides (ion recombination) are ~2 × 1010 M-1 s-1 (diffusion control). The radicals C? disappear by dimerization and disproportionate, for which a complete mass balance has been achieved by product analysis for the case of the benzhydryl system. At laser-pulse powers > 10 mJ electronically excited radicals, C?*, are additionally formed in many cases, via absorption of a light quantum by ground-state C?.
- Bartl,Steenken,Mayr,McClelland
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p. 6918 - 6928
(2007/10/02)
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- Redox-photosensitised Reactions. Part 12. Effects of Magnesium(II) Ion on the 2+ -Photomediated Reduction of Olefins by 1-Benzyl-1,4-dihydronicotinamide: Metal-ion Catalysis of Electron Transfer Processes Involving an NADH Model
-
Magnesium(II) ion catalyses the photosensitised reduction of carbon-carbon double bonds of dimethylfumarate, derivates of methyl cinnamate, and some other related olefins by 1-benzyl-1.4-dihydronicotinamide (BNAH), which proceeds via sequential two electron transfer initiated by the photoexcitation of +2 (bpy = 2,2'-bipyridine).The metal ion forms a complex with BNAH in methanol as well as in 10:1 (v/v) pyridine-methanol, leading to the retardation of electron transfer from BNAH to luminescent excited-state Ru(ppy)32+.The net metal-ion effects arise from the catalysis of both the first and second one-electron reduction processes.
- Ishitani, Osamu,Ihama, Mikio,Miyauchi, Yoji,Pac, Chyongjin
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p. 1527 - 1532
(2007/10/02)
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- Redox-Photosensitized Reactions. 11. Ru(bpy)32+-Photosensitized Reactions of 1-Benzyl-1,4-dihydronicotinamide with Aryl-Substituted Enones, Derivatives of Methyl Cinnamate, and Substituted Cinnamonitriles: Electron-Transfer Mechanism and Structure-Reactivity Relationship
-
Reactions of 1-benzyl-1,4-dihydronicotinamide (BNAH) with aryl-substituted enones and derivatives of methyl cinnamate and cinnamonitrile (1a-u) are photosensitized by Ru(bpy)32+ (bpy = 2,2'-bipyridine).The reduction of carbon-carbon double bonds commonly requires the substitution of either an electron-withdrawing aryl group or two phenyl groups at the β-carbon atom of 1.With enones which possess one aryl substituent with no extra electron-withdrawing group at the β position, the photosensitized reactions result in no two-electron reductions but give 1:1 adducts (4d-h) along with half-reduced dimers of olefins (3d and 3g) and a half-oxidized dimer of BNAH (5).The observed results can be easily interpreted by assuming the intervention of 1-benzyl-3-carbamoyl-1,4-dihydropyridin-4-yl radical (BNA.) and half-reduced species (.1-H) as key intermediates that are formed by mediated electron-proton transfer from BNAH to 1 in which Ru(bpy)32+ acts as a one-electron shuttle upon photoexcitation in the initial electron transfer.Whether BNA. undergoes electron transfer to or a radical-coupling reaction with .1-H depends on steric and electronic properties of .1-H which should be affected by the substituents at the radical center.Mechanistic implications for thermal reactions of NADH models with olefins in the dark are briefly discussed on the basis of these observations.
- Pac, Chyongjin,Miyauchi, Yoji,Ishitani, Osamu,Ihama, Mikio,Yasuda, Masahide,Sakurai, Hiroshi
-
-
- Electroreductive Cyclopropylcarbonylation of Aromatic Ketones and Their Schiff Bases
-
Mono- and dicyclopropylcarbonyl derivatives have been obtained by electroreduction of fluorenone, benzophenone, fluorenone anil, and benzophenone anil in the presence of 1 equiv of 4-bromo(or chloro)butyryl chloride (1a or 1b).The electrolyses are carried out in DMF or MeCN according to two methods.In method A, 1a (or 1b) is added dropwise during the electrolysis.In method B, the total amount of 1a (or 1b) is added at the beginning of the experiment.The electrogenerated bases which are necessary to perform the cyclopropylcarbonylation reactions are either theradical anions of the depolarizers or their acylated anions.The distribution of the compounds and their yields, which are moderate, depend on two main factors which are the method applied and the solvent.It is shown that the properties of acid chlorides 1a and 1b differ in DMF and MeCN.The highest yields of cyclopropyl derivatives are reached in MeCN when method B is applied.However, in this solvent the acylation reaction is less specifically orientated than in DMF, and unexpected propionitrile derivatives are isolated.In the case of the anils, results of chemical reduction by alkali metals and electrochemical reduction are compared.
- Belot, Gerard,Degrand, Chantal,Compagnon, Paul-Louis
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p. 325 - 331
(2007/10/02)
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- Cyanomethylation during the Electroreduction of Aromatic Carbonyl Compounds in Acetonitrile
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The formation of substituted 3-hydroxy-3-phenylpropiononitriles (II), cinnamonitriles (III), 3-phenylpropiononitriles (IV), and 3-phenylglutaronitriles (V) during the electroreduction of acetophenone, benzaldehyde, and benzophenone in acetonitrile has been studied.The factors which influence the distribution of these products and their importance relative to the 'normal' reduction products, pinacols (VII) and carbinols (VIII), have been identified; current density, temperature, and water concentration are the most important.The distribution of acetonitrile-derived products is compared with that found when the corresponding cinnamonitriles (III) are electroreduced.
- Abbot, Elaine M.,Bellamy, Anthony J.,Kerr, John B.,MacKirdy, Iain S.
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p. 425 - 430
(2007/10/02)
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- COMPARATIVE REACTIVITY OF NITRILES OF PARA-SUBSTITUTED CINNAMIC ACIDS IN THE ALKYLATION OF BENZENE IN THE PRESENCE OF ALUMINUM CHLORIDE
-
The relative rate constants for the reactions of the nitriles of p-methoxy, p-methyl, and p-chlorocinnamic acids with benzene in the presence of aluminum chloride were determined by the method of competing reactions in relation to cinnamonitrile.The negative sign of ρ indicates that the electrophilic stage of complex formation between the unsaturated nitrile and aluminum chloride has a deciding role in the alkylation process.
- Grebenyuk, A. D.,Grinshpun, V. D.,L'vov, V. M.
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p. 732 - 736
(2007/10/02)
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