Novel Activated Carbon Fiber Solid-Phase Microextraction for Determination of Benzyl Chloride and Related Compounds in Water by Gas Chromatography–Mass Spectrometry

An activated carbon fiber (ACF) has been developed for use as an extraction fiber in solid-phase microextraction (SPME) and used to determine benzyl chloride, benzyl dichloride, and benzyl trichloride in water samples by headspace (HS) analysis. Experiments showed that ACF has excellent adsorption capacity. Its well-distributed surface makes desorption swift in a GC–MS injector. Several conditions affecting the ACF-SPME procedure, for example adsorption mode, adsorption time and temperature, and desorption time, were optimized. The optimized HS-ACF-SPME method has acceptable linearity, good precision, and reasonable RSD values for the compounds studied. The ACF is, therefore, a promising alternative for SPME.     

Five-, Six-, and Seven-membered Lactim Ethers. Methods of Synthesis and Chemical Properties. (Review)

Data on methods for the production of 5–7-membered lactim ethers and their chemical transformations published after 1970 are reviewed.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 645–690, May, 2005.     

Cucurbit[6]uril as Ligand for the Complexation of Diamines, Diazacrown Ethers and Cryptands in Aqueous Formic Acid

The complex formation between cucurbit[6]uril and different diamines, diazacrown ethers, and cryptands has been studied in aqueous formic acid solution. The complex stabilities and the thermodynamic values for the complex formation of diamines are reduced if any further donor atom (e.g., sulfur, oxygen, or nitrogen) is present in the molecules. The inclusion of this polar group inside the cavity of cucurbit[6]uril has a negative effect upon the complex formation. Diazacrown ethers and cryptands do not form inclusive complexes. One nitrogen donor atom interacts with the carbonyl groups at one of the portals.     

Organic chemosensors with crown-ether groups (review)

Recent advances in the chemistry of organic chemosensors containing crown-ether groups are reviewed. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1123–1151, August, 2008.     

Enantioselective Phase Transfer Catalytic Reactions. A Comparative Study on the Use of Cinchonidine Salts and Glucose-Based Lariat Ethers Including Phosphinoxidomethyl Derivatives

Five model reactions including an epoxidation by alkylhydroperoxide or Darzens condensation, as well as Michael additions were accomplished under phase transfer catalytic conditions using cinchonidine salts or lariat ethers with side arms having HO or Ph₂P(O) endgroups as the catalysts. In almost all cases, the use of lariat ethers with either hydroxyalkyl- or phosphinoxido N-substituents led to better enantioselectivities than that of the three cinchonidine derivatives studied.     

Regioselective synthesis of 2-acetyl- and 2-alkoxycarbonyl-3-(trifluoromethyl)phenols by [3+3] cyclization of 1,3-bis-silyl enol ethers with 4-ethoxy- and 4-silyloxy-1,1,1-trifluoroalk-3-en-2-ones

2-Acetyl- and 2-alkoxycarbonyl-3-(trifluoromethyl)phenols were prepared by [3+3] cyclization of 1,3-bis-silyl enol ethers with 4-ethoxy- and 4-silyloxy-1,1,1-trifluoroalk-3-en-2-ones.     

Domino synthesis of indenols and alkyl-indene ethers under modified Vilsmeier conditions

Indenols are produced in high yields through domino reactions, when electron-rich trans-stilbenes and other trans aryl-alkyl olefins were subjected to Vilsmeier formylation in the presence of excess POCl₃ in a one-pot procedure. The method is even suitable for converting aryl-alkyl carbinols (precursors for olefins) directly into indenols. The corresponding indene ethers could be prepared in high yields directly when less reactive α,β-unsaturated aldehydes were subjected to cyclization in alcoholic HCl.