Xi:Irritant;
104-85-8Relevant articles and documents
Photochemical equilibration/isomerization of p-, m-, and o-methylbenzonitrile
MacLeod, Paula J.,Pincock, Alexandra L.,Pincock, James A.,Thompson, Kim A.
, p. 6443 - 6450 (1998)
The phototransposition reactions in acetonitrile of p-, m-, and o-methylbenzonitrile have been studied. Any one of the three is converted to the other two by either a 1,2- or 1,3-isomerization in a primary photochemical step. However, the reactivities are quite different with the relative values for para:meta:ortho = 32:4:1. For both the para and meta isomers, extended irradiations approach a calculated steady-state composition of para:meta:ortho = 3:20:77. Quenching of the excited triplet state of the para and meta isomers with 2,4-dimethyl-1,3-butadiene indicates that these reactions are occurring from the excited singlet state. Irradiation of selectively labeled 2,6-dideuterio-4-methylbenzonitrile demonstrates that only the cyano-substituted carbon undergoes migration.
Reusable, highly active heterogeneous palladium catalyst by convenient self-encapsulation cross-linking polymerization for multiple carbon-carbon cross-coupling reactions at ppm to ppb palladium loadings
Donga, Zhongmin,Yea, Zhibin
, p. 3401 - 3414 (2014)
Designing reusable high-performance heterogeneous palladium (Pd) catalysts via convenient, economic synthesis is of great importance to the industrial applications of various carbon-carbon crosscoupling reactions. We demonstrate herein a convenient one-pot self-encapsulation synthesis of a heterogeneous Pd catalyst [Pd@PDEB, PDEB = poly(1,3-diethynylbenzene)] directly from commercially available, economic precursors. In the synthesis, the formation of the cross-linked polymer networks and Pd encapsulation are accomplished simultaneously, turning a homogeneous Pd polymerization catalyst into the heterogeneous cross-coupling catalyst. As a unique, practical heterogeneous catalyst, Pd@PDEB shows remarkably high activity, high reusability, and high versatility towards at least four types of cross-coupling reactions (Suzuki-Miyaura, Stille, allylic arylation, and Mizoroki-Heck reactions) with even difficult reactants (aryl chlorides and heteroaryl halides) under aerobic conditions with Pd loadings down to ppm or even ppb levels. Evidences from hot filtration and 3-phase tests demonstrate the heterogeneous nature of the catalyst with very low Pd leaching and negligible contributions of leached homogeneous Pd species towards the coupling reactions.
Isomerization of Methylbenzonitriles Catalysed by HZSM-5
Weigert, Frank J.
, p. 2653 - 2655 (1986)
The zeolite HZSM-5 catalyzes methyl migration in toluonitriles and dimethylbenzonitriles by intramolecular 1,2-shifts.Only the three dimethylbenzonitriles with 1,2,4-substituent pattern are small enough to take part in the shape selective reaction.
Dichlorobis(triphenylphosphine)nickel-catalyzed cross-coupling of aryl chlorides with intramolecularly stabilized group 13 metal alkylating reagents
Gelman,Schumann,Blum
, p. 7555 - 7558 (2000)
The intramolecularly stabilized alkyl and aryl aluminum complexes 1, 4 and 11, as well as the indium compounds 6, 9 and 10 cross-couple with a variety of chloroarenes at 8°C in the presence of NiCl2(PPh3)2 to give selectively the respective alkylated arenes in high yields. Addition of organic or inorganic bases lowers the reaction temperature to 50°C. (C) 2000 Elsevier Science Ltd.
Cul/1,10-phenanthroline: An efficient catalyst system for the cyanation of aryl halides
Zhu, Yi-Zhong,Cai, Chun
, p. 484 - 485 (2007)
Aryl nitriles have been prepared in good yields from the corresponding aryl halides with potassium hexacyanoferrate(II) using Cul/1,10-phenanthroline as the catalyst system. Furthermore, the reaction is compatible with a wide range of functional groups including nitro and carbonyl substituents.
Cu-mediated nitrogen atom transfer via C≡N bond cleavage
Liu, Lixin,Dong, Jianyu,Zhang, Yaxing,Zhou, Yongbo,Yin, Shuang-Feng
, p. 9948 - 9952 (2015)
A nitrogen atom transfer to organic molecules via Cu-mediated C-N triple bond cleavage is firstly developed, which provides a variety of functionalized aryl nitriles from the readily accessible acetonitrile and aryl aldehydes.
Simple and efficient one-pot synthesis of nitriles from amides and oximes using in situ-generated burgess-type reagent
Rappai, John P.,Karthikeyan, Jayakumar,Prathapan, Sreedharan,Unnikrishnan, Perupparampil A.
, p. 2601 - 2606 (2011)
The dehydration of aldoximes and amides, and oxidation of benzoin are accomplished in one-pot using in situ-generated Burgess-type reagent. Taylor & Francis Group, LLC.
A versatile method for the conversion of aldoximes to nitriles using silica gel/thionyl chloride
Kazemi, Foad,Kiasat, Ali Reza,Fadavipoor, Elham
, p. 433 - 436 (2004)
A simple convenient procedure for dehydration of aldoximes has been developed using silica gel/thionyl chloride in heterogeneous conditions. The method has been found to be effective for a wide range of aromatic oximes.
Activation energies for the singlet excited state processes of substituted benzenes: Para, meta, and ortho isomers of methylbenzonitrile and methylanisole in acetonitrile
Gonzalez, Carlos M.,Pincock, James A.
, p. 8870 - 8871 (2004)
The rate constants of decay of the excited singlet states of the methylbenzonitriles (1-3) and the methylanisoles (4-6) have been determined by the measurement of fluorescence lifetimes over a broad range of temperatures (-45 to +65 °C) in acetonitrile. By fitting this data to a nonlinear expression that includes the Arrhenius equation, rate constants for the activated process (reaction) and the unactivated ones (fluorescence and intersystem crossing) can be reliably obtained. Available literature data for benzene, toluene, and ortho-xylene were also analyzed. The results indicate that the excited singlet state of substituted benzenes is quite reactive and forms a prefulvene biradical intermediate efficiently (quantum yield = 0.69 for benzene itself) by an activated route. In contrast, the efficiency of isolable product formation is quite low because the dominant process for this intermediate is returned to starting material. These observations explain why Ermolaev's rule does not apply to benzene derivatives. Copyright
An efficient and convenient KF/Al2O3 mediated synthesis of nitriles from aldehydes
Movassagh, Barahman,Shokri, Salman
, p. 6923 - 6925 (2005)
KF/Al2O3 brings about a facile one-pot and economical conversion of various aryl and alkyl aldehydes into the corresponding nitriles in high yields by reaction with hydroxylamine hydrochloride.
