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1.
Condensation of N-substituted 5-aminopyrazoles with -diketones occurs with the formation of pyrazolo[4,5-b]pyridines. Depending on the conditions, their reaction with -keto acids can give either 6-oxo- or 4-oxopyrazolo[4,5-b]pyridines. 相似文献
2.
As a result of a continuing study utilizing nitrogenous bases2–6, we now wish to report that the base 3-quinuclidinol (13) is useful for the cleavage of β-keto and vinylogous β-keto esters. 相似文献
3.
Massimo Gianotti Giorgio Martelli Giuseppe Spunta Eileen Campana Mauro Panunzio Monica Mendozza 《合成通讯》2013,43(10):1725-1730
Microwave technique has been utilised in the preparation of β-keto esters. Two different procedures are described: transesterification of β-keto esters and ring opening of 2,2,6-trimethyl-1,3-dioxin-4-one. 相似文献
4.
A pH-independent asymmetric transfer hydrogenation of β-keto esters in water with formic acid/sodium formate is described. The reaction is conducted open to air and gives access to β-hydroxy esters in excellent yields and selectivities. 相似文献
5.
A series of Cu(II), Co(II), Mn(II), Fe(III), and La(III) chelates with unsymmetrical fluorinated -keto esters, taken separately and in mixtures with tertiary amines, were tested as catalysts in urethane formation and in synthesis of network elastomers. 相似文献
6.
XIAO Li-wei ZHANG Min SUN Wen-hua . Faculty of Chemistry Material Science Langfang Teachers College Langfang P. R. China . Key Laboratory of Engineering Plastics Beijing National Laboratory for Molecular Sciences 《高等学校化学研究》2011,(2):228-231
An efficient synthetic method was developed to synthesize 2-substituted benzimidazoles and benzo- xazoles with β-keto esters as starting materials under mild reaction conditions, during which other functional groups are bearable from reactants to products. 相似文献
7.
Selective α-Bromination of β-Keto Esters in Reusable PEG-400 under Mild and Catalyst-free Conditions
An efficient bromination protocol for the synthesis of α-bromo-β-keto esters has been developed. In PEG-400 (poly(ethylene glycol-400)), a variety of β-keto esters were treated with NBS (N-bromosuccinimide) at room temperature to selectively afford the corresponding α-monobromination products in excellent yields. It is noteworthy that the reaction was conducted under mild, environmentally benign and catalyst-free conditions. 相似文献
8.
A. V. Astakhov R. I. Zubatyuk R. S. Abagyan V. M. Chernyshev 《Chemistry of Heterocyclic Compounds》2014,49(10):1500-1507
9.
E. K. Panisheva L. M. Alekseeva A. S. Shashkov V. G. Granik 《Chemistry of Heterocyclic Compounds》2003,39(8):1013-1017
Benzofuranone derivatives have been synthesized by the condensation of p-benzoquinone with anilides of -aminocrotonic acids under the conditions of the Nenitzescu reaction. 相似文献
10.
Polyfluorinated 2-arylpyrimidines were synthesized by the reaction of polyfluorinated -diimines with aromatic aldehydes. 相似文献
11.
An efficient procedure for the synthesis of β-keto esters from the reaction of aldehydes and ethyl diazoa-cetate catalyzed by iodine at room temperature under solvent-free conditions has been described. The catalytic procedure has the advantages of easily available catalyst,mild reaction conditions,high yields,and easy work-up. 相似文献
12.
13.
14.
A synthesis of β-stannyl esters from ester enolates and iodomethyl (tri-n-butyl) stannane (3) is described. 相似文献
15.
Wei-Chen Zhu Yi-Fan Jiang Xin-Yu Liu Shi-Yin Tian Prof. Weidong Rao Prof. Shu-Su Shen Assoc. Prof. Ping Song Dr. Daopeng Sheng Prof. Shun-Yi Wang 《European journal of organic chemistry》2023,26(25):e202300379
A photoinduced synthesis of β-keto thiosulfone/β-keto selenosulfone by the reaction of α-bromoacetophenone with thiosulfonate/selenosulfonate under metal-free and visible light irradiation conditions is developed. Two C−S bonds or one C−S bond and one C−Se bond were constructed simultaneously. 相似文献
16.
Charles F. Beam Ronda M. Sandifer Robert S. Foote Charles R. Hauser Paul M. Gross 《合成通讯》2013,43(1):5-10
In addition to our previous papers2,3 on the preparation of pyrazoles from the C(α), N-dianions of phenylhydrazones and C(α), N, N-trianions of hydrazones, we wish to report preliminary results on (I) the preparation and condensation of methylhydrazone dianions with methyl benzoate followed by acid cyclization, (II) the condensation of the dianions of phenylhydrazone with methylformate, and the preparation and condensation of the trianions of cyclopentanone (III) and α - tetralone (IV) hydrazones. 相似文献
17.
I. P. Lokot' F. S. Pashkovskii F. A. Lakhvich 《Chemistry of Heterocyclic Compounds》2001,37(6):707-714
A method is proposed for obtaining 3- and 5-alkyl-6-alkyl(aryl)tetrahydropyran-2,4-diones based on the condensation of the dianion of alkyl(dialkyl)acetoacetic ester with aldehydes and ketones. 相似文献
18.
Transesterification of β-keto esters with a wide variety of allyl, benzyl, propargyl, and alkyl alcohols using, for the first time, commercially available and inexpensive Et3N as a Brønsted base additive, is efficiently performed in toluene at reflux. The corresponding esters are exclusively obtained in 57–98% yields with no trace amounts of γ,δ-ketones, usually expected from the decarboxylative Carroll rearrangement. 相似文献
19.
2-Methyleneaminonaphthalene smoothly reacts with cyclic -diketones to afford azaphenanthrene derivatives in high yield. The dihydropyridine ring in the products can be oxidized to pyridine ring. The oxidation products, unlike their precursors and analogs having an aryl substituent in the -position with respect to the nitrogen atom, react with hydroxylamine at the carbonyl group to give the corresponding oximes and in some cases undergo Knoevenagel condensation with malononitrile. Hydrolysis of the condensation product yields the respective diamide. 相似文献