Reaction of silyl enol ethers with cyanogen chloride

Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1447–1448, June, 1988.     

Reaction of octafluorocyclopentene with various carbon nucleophiles

The treatment of octafluorocyclopentene with organolithium reagents gave the corresponding symmetrical disubstituted perfluorocyclopentenes in good to high yields. The reaction with Grignard reagents led to the monosubstituted perfluorocyclopentenes, which were subjected to the further nucleophilic substitution reaction using another Grignard or aryllithium reagents, unsymmetrical disubstituted perfluorocyclopentenes being obtained in high yields.     

Efficient methodology for alkylation of vinylnitroso compounds with carbon nucleophiles

A diverse array of nitrosoalkenes derived from both acyclic and cyclic ketones, as well as aldehydes, via the Denmark protocol using α-chloro-O-TBS-oximes can be trapped efficiently in situ by a wide variety of potassium ester enolates to afford conjugate addition products in good yields.     

Reaction of 1,3-dicarbonyl compounds with nitryl chloride

Reaction of 1,3-dicarbonyl compounds with nitryl chloride through substitution on the activated methylene group, resulted in the formation of chloro, dichloro and oximino derivatives.

---

Die Reaktion der 1,3-Dicarbonylverbindungen mit Nitrylchlorid

Zusammenfassung Umsetzung von 1,3-Dicarbonylverbindungen mit Nitrylchlorid ergab die entsprechende Chloro-, Dichloro- und Oximinoderivate in einer Substitutionsreaktion an der aktivierten Methylengruppe.

     

Reaction of perfluoroalkylethylens with nucleophiles

Perfluoroalkylethylenes react with some carbon-, oxygen-, sulfur-, selenium-, nitrogen-, and phosphorus-based nucleophiles by formal S_N2′ displacement of fluoride ion.     

Determination of cyanogen and cyanogen chloride using gas chromatography with a flame ionisation detector

Summary The response of a flame ionisation detector (FID) to cyanogen ((CN)₂) and cyanogen chloride (CNCI) has been studied. The lower limits of detection for (CN)₂ and CNCl were 6×10⁻¹² moles and 2×10⁻¹¹ moles respectively. In a comparative study a thermal conductivity detector gave as its lower limit of detection for both (CN)₂ and CNCl 4×10⁻¹¹ moles. Both detectors showed excellent linearity over the range 0 to 10 micromoles. The ratio of the gradients of the FID calibrations (CN)₂/CNCI were found to be approximately two suggesting the response depended on the cyanide group. The response and stability of the FID was investigated as a function of air and hydrogen flow-rates. The response increased with increasing air flow-rate for both (CN)₂ and CNCI up to 300cm³min⁻¹, thereafter no significant increase was observed. On raising the hydrogen flow from 10 to 25cm³min⁻¹ only a slight increase in the sensitivity of the FID towards both (CN)₂ and CNCI was observed. At higher flow rates the response for (CN)₂ increased markedly whereas at the same flow rates the response for CNCI increased only slightly.     

Electroauxiliary-assisted sequential introduction of two carbon nucleophiles on the same alpha-carbon of nitrogen: application to the synthesis of spiro compounds

The sequential introduction of two carbon nucleophiles on the same alpha-carbon of nitrogen by using selective oxidative cleavage of two silyl groups as electroauxilialies has been accomplished. The combination of this expedient transformation and ring-closing metathesis enables reliable and straightforward syntheses of nitrogen-containing spiro compounds, such as cephalotaxine.     

Reaction of N,N-dimethylselenocarbamoyl chloride with nucleophiles. Preparation of diselenocarbamates, selenothiocarbamates, and selenoureas

Reactions of N,N-dimethylselenocarbamoyl chloride prepared by using LiAlHSeH with nucleophiles such as lithium alkylselenolate, lithium alkylthiolate, and amines afford the corresponding diselenocarbamates, selenothiocarbamates, and selenoureas. The crystal structure of the Se-phenyl N,N-dimethyldiselenocarbamate was also determined by X-ray diffraction.     

Reaction of 4-methyl-3,4-epoxytetrahydropyran with nucleophiles

Reaction of 4-methyl-3,4-epoxytetrahydropyran with phenols, thiols, thiocyanic acid and benzoic acid, thiourea, and with sodium sulfite and thiosulfate occurs with opening of the epoxide ring. Using IR spectroscopy it was shown that the products occur via trans-diaxial opening of the oxide ring at the least-substituted carbon atom.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1465–1468, November, 1990.     

Palladium-catalyzed carbene insertion and trapping with carbon nucleophiles

Palladium catalysts are shown to catalyze the three-component coupling of vinyl halides, trimethylsilyldiazomethane, and stabilized carbon nucleophiles. The reaction is believed to proceed through a palladium-carbene intermediate LX(R)PdCHSiMe 3 that undergoes migration of the vinyl substituent to the electrophilic carbene center to generate an eta 3-allylpalladium intermediate. The allylpalladium intermediate is attacked by the carbon nucleophile to generate a vinylsilane product.     

Reactions of carbon nucleophiles with 2,2,3-trisubstituted ethynylaziridines

Carbon nucleophiles were used to open a 2,2,3-trisubstituted ethynylaziridine. A cyanide nucleophile opened the ring at the more substituted carbon, proceeding regioselectively with inversion of configuration. In an attempt to expand upon the scope of the reaction, Normant cuprates were reacted with a 2,2,3-trisubstituted ethynylaziridine. This reaction produced chiral allenes via an anti-S_N2′ pathway. X-ray analysis of a derivative allowed the absolute stereochemistry of the anti-allenes to be assigned as P.     

多氟代烃类的反应II: 氟氯烯烃与三氯化铝的反应

研究了以CFCl2CF2CF=CF2(1)和CFCl2CF=CFCF2(2)为原料与三氯化铝的反应.结果获得重排产品CCl2=CF2CF2CF3(3).结果支持了从1到3的分子间重排反应的机理.在激烈条件下,3进一步与氯化铝反应得到CCl2=CFCCl2CF3(4),CCl2=CClCCl2CF3(5),CCl2=CClCCl2CClF(6),CCl2=CClCCl2CFCCl2(7)和CCl2=CClCCl2CCl3(8).由分离所得产品的结构可推断化合物3中氟原子被氯原子取代的稳定性按以下次序:CF3->CF=>=-CF2CF=.反应条件对产品得率的影响也被讨论了.     

Graphene oxide as an electrophile for carbon nucleophiles

The covalent, surface functionalization of graphene oxide with the malononitrile anion has been demonstrated. Once installed, these surface-bound "molecular lynchpins" can be chemically modified to increase the solubility of the graphene derivative in either organic or aqueous environments.     

Reaction of sulfolenes and their derivatives with some sulfur-containing nucleophiles

Reaction of 2-sulfolene, 4-hydroxy-2-sulfolene, 4-bromo- and 3-chloro-2-sulfolenes, 3-chloro-4-hydroxysulfolane, and 3,4-dibromo(dichloro)sulfolanes with sodium methane-, hexane-, allene-, benzene-, and p-toluenesulfinates and magnesium gave 3-methyl-, 3-hexyl-, 3-allyl-, 3-phenyl-, and 3-(p-tolylsulfonyl)sulfolanes, 3-methyl-, 3-phenyl-, and 3-(p-tolylsulfonyl)-4-hydroxysulfolanes, and 3-phenyl- and 4-phenylsulfonyl-2-sulfolenes.