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51.
52.
A three-component reaction of the zwitterions generated from isocyanides and dialkyl acetylenedicarboxylate with 1-(4-bromophenyl)-2-thiocyanatoethanone or 1-phenyl-2-thiocyanatoethanone is described. The reaction afforded the corresponding special type of functionalized iminolactone derivatives in good yields at room temperature without using a catalyst.  相似文献   
53.
The zwitterionic intermediate generated from the reaction of triphenylphosphine with electron deficient acetylenic compounds was trapped by various NH acids. The synthesis resulted in a new class of highly functionalized heterocyclic compounds. Some of the reactions produced E and Z isomers. And the stability and transformation of them were studied by dynamic 1H NMR and density functional theory (DFT) calculations.  相似文献   
54.
In this study, a three-component one-pot synthesis of new 2,4-diamino-5H-chromeno[2,3-b]pyridine-3-carbonitriles derived from 2-amino-1,1,3-tricyanopropene, salicylic aldehydes and secondary cyclic amines is reported. The reaction is conducted in ethanol at ambient temperature in good-to-excellent yields.  相似文献   
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56.
Summary. The three-component condensation of aldehyde, N,N′-dimethylbarbituric acid and alkyl or aryl isocyanide afforded the corresponding furo[2,3-d]pyrimidine-2,4(1H,3H)-diones in 1-butyl-3-methylimidazolium bromide as an ionic liquid in high yields at room temperature within several minutes.  相似文献   
57.
1-Butyl-3-methyl-imidazolium chloride ([bmim]Cl) in the absence of any catalyst mediated the selective deprotection of benzyl and phenyl trimethylsilyl (TMS) ethers to the corresponding alcohols and phenol in good yields at room temperature even in presence of alkyl silyl ethers. The work-up of reactions is very simple and the products do not require further purification. The ionic liquid (IL) can be recycled and reused for several runs without any significant loss of activity.  相似文献   
58.
Ammonium chloride as a very inexpensive and readily available reagent efficiently catalyzes one-pot, three-component Groebke condensation reactions of aldehydes, isocyanides, and 2-aminopyridines or 2-aminopyrimidines in methanol to afford the corresponding imidazo[1,2-a]pyridines in high yields at room temperature. Correspondence: Ahmad Shaabani, Department of Chemistry, Shahid Beheshti University, PO Box 19396-4716, Tehran, Iran.  相似文献   
59.
The direct conversion of alpha-hydroxy ketones and alpha-keto oximes into quinoxaline derivatives in the presence of a catalytic amount of ceric ammonium nitrate via metal-catalyzed aerobic oxidation followed by in situ trapping with aromatic 1,2-diamines in water as a green and efficient reaction media, is reported.  相似文献   
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