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41.
A straightforward and efficient method has been developed for the synthesis of α‐aminonitriles by combining aldehydes, amines and trimethylsilyl cyanide in the presence of a catalytic amount of thallium(III) chloride tetrahydrate (1 mol%) under solvent‐free conditions at room temperature. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
42.
A. Davoodnia M. Bakavoli M. Soleimany H. Behmadi 《中国化学快报》2008,19(6):685-688
A new one-pot neat synthesis of some 5-aryl-2,4-dihydro-3H- 1,2,4-triazol-3-ones through cyclocondensation of ethyl carbazate with aryl nitriles catalyzed by DMAP as an efficient and basic nucleophilic catalyst is described. 相似文献
43.
Mário A. Marangoni Carlos E. Bencke Helio G. Bonacorso Marcos A.P. Martins Nilo Zanatta 《Tetrahedron letters》2017,58(43):4057-4061
A new, simple, and efficient method for the synthesis a novel series of 1-substituted 4-(trifluoromethyl)-5-(alkan-1-ol)-pyridin-2(1H)-imines from the reaction of 3-(5,6-dihydro-4H-pyran-3-yl)-4,4,4-trifluorobut-2-enenitrile and 3-(4,5-dihydrofuran-3-yl)-4,4,4-trifluorobut-2-enenitrile with primary amines – is described. The products were obtained in 29–82% yield. 相似文献
44.
Tertiary aliphatic β- and γ-nitro nitriles and ketones deuterated in (several) selected positions had been synthesized. The deuterated nitro compounds served as a starting material for the corresponding deuterium labeled nitrones or hydroxylamines (reducing with aluminum amalgam). Further oxidation of the last two groups of compounds with sodium periodate or m-CPBA afforded the relevant deuterated tertiary C-nitroso compounds. 相似文献
45.
Substituted five-membered cyclic nitrones (pyrroline N-oxides) have been obtained in good to high yields from tertiary γ-nitro ketones and nitriles employing aluminium amalgam as a reducing agent in moist diethyl ether or THF. Attempts to obtain cyclic amino nitrones from α- or β-nitro nitriles failed and only the corresponding hydroxylamines have been isolated. Both nitrones and hydroxylamines have been used for synthesis of tertiary C-nitroso nitriles or ketones. 相似文献
46.
Irina Iovel Lena Golomba Sergey Belyakov Andrejs Kemme Edmunds Lukevics 《应用有机金属化学》2001,15(9):733-743
A series of novel Shiff bases (1a–h) was synthesized by condensation of pyridinecarboxaldehydes (1–4) with 3‐ and 4‐trifluoromethylanilines (5, 6) in the presence of molecular sieves (4 Å). It was found that AlCl3 and AlBr3 catalyzed the addition of Me3SiCN to the C?N bond of the imines obtained, whereas the other Lewis acids studied (YCl3, LaCl3, ZnI2) were not active. The reactivity of the imines in the title reaction, on the whole, correlated with their basicity. Besides the addition giving the expected α‐amino nitriles (2a,b,d–f,h), an unusual reaction leading to unsaturated nitriles (3a–h) was observed. The structures of saturated and unsaturated products 2d and 3c were determined by X‐ray diffraction. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
47.
The nitrile functional group is efficiently transformed into the β-ketosulfoxide moiety by reaction with the anion formed from (+)-(R)-methyl p-tolyl sulfoxide and aqueous acidic work-up of the reaction. 相似文献
48.
Data on 1,3-dipolar cycloaddition of nitrones to free and coordinated nitriles producing 2,3-dihydro-1,2,4-oxadiazoles (or
Δ4-1,2,4-oxadiazolines) are summarized. The latter compounds belong to the virtually unknown class of heterocyclic systems.
The main factors responsible for the cycloaddition reactions are discussed. Particular attention is given to the role of metal
centers in controlling the synthesis of 2,3-dihydro-1,2,4-oxadiazoles.
Dedicated to Academician O. M. Nefedov on the occasion of his 75th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1803–1815, November, 2006. 相似文献
49.
Catalytic Enantioselective Reaction of α‐Phenylthioacetonitriles with Imines Using Chiral Bis(imidazoline)–Palladium Catalysts 下载免费PDF全文
Masaru Kondo Natsumi Kobayashi Prof. Dr. Tsubasa Hatanaka Prof. Dr. Yasuhiro Funahashi Prof. Dr. Shuichi Nakamura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(25):9066-9070
The catalytic enantioselective reaction of α‐phenylthioacetonitriles with imines has been developed. The reaction of various imines proceeds in good yields and diastereo‐ and enantioselectivities in the presence of chiral bis(imidazoline)–palladium catalysts. The obtained products can be converted into β‐aminonitrile or β‐aminoamide compounds without loss of enantiopurity. 相似文献
50.
《Angewandte Chemie (International ed. in English)》2017,56(38):11645-11648
Diboration of unsaturated organic compounds is an extremely useful reaction in synthetic chemistry. Herein, we report the first diboration of a nitrile by an electron‐rich diborane, mediated by an electrophilic borane. The reaction is metal‐free, and all of the reagents are readily available. 相似文献