Thin layer chromotography

Usually the benzyl ether is dissolved in EtOH and cyclohexene, and 20% Pd(OH)2/C is added (1 10 catalyst-substrate by weight) and stirred under reflux for the required period (thin layer chromotography monitoring).246 Without cyclohexene, the benzyl ether was usually recovered, signifying that the EtOH solvent is not a good hydrogen donor under these conditions. 

The thin-layer chromotography (TLC) monitoring of the reaction (Scheme 28) leads to a conclusion that the anomalous l-vinyl-2-methylpyrrole (53) is a secondary product from the pyrrole (54). When reacting with excess acetylene in an autoclave at 100°C, l-hydroxy-2-methyl-3-butanone oxime (55) gives two anomalous products, 2,3-dimethyl-1-vinylpyrrole (56), which was also reported (78IZV2426), and 2-(l-propeny 1-2)-1-vinylpyrrole (57) in 20 and 8% yields respectively (Scheme 28). 

Thin Layer Chromotography. Unless otherwise stated, all thin layer chromotography was on plates coated with silica Gel G (E. Merck, Dramstadt). All the solvents were mixed on a volume basis. Neutral glycolipid fractions were developed in chloroform methanol water (60 35 6.5). Labelled fucolipid fractions were developed in chloroform methanol water (40 40 10). For separation of gangliosides, chloroform methanol 2.5N aqueous NH4OH (60 40 9) was used. 

Pure quinizarin was also Identified as a component of the hydrolyzate by thin layer chromotography. 

Gurfinkal, D.M., and U.M. Franklin. 1985. The analysis of organic archaeological residue an evaluation of thin layer chromotography. In Archaeometry Proceedings 85-88. 

The transient formation of benzyl radical XXXIX has been assumed even in oxidation of 2,2 -methylenebis (4-methyl-6-tert-butylphenol) XXXVII by radicals tert-BuO or tert-BuO 249)- A phenolic dimer XL and a trimer XLVI arise as the main reaction products with a molar ratio of biphenol XXXVII to an oxidation agent of 1-2 1. The presence of further two phenolic compounds and several dark-coloured products, which strongly discolour the reaction mixture, was ascertained in the reaction mixture by means of thin-layer chromotography (TLC). The Scheme 6 was proposed to describe the oxidation transformations of XXXVII under conditions simulating the inhibition process. It comprises (a) the formation of phenoxyl XXXVIII, its rearrangement to the benzyl radical XXXIX and dimerisation to XL, (b) the direct formation of XXXIX followed by dimerization, and (c) the dis-... 

A portion of the organic by-products was dissolved in carbon tetrachloride or chloroform (spectroscopic grade) for infra-red cuialysis. The absorption peaks corresponded to nitrophenols, nitrocresols, dinitrophenols, dinitrocresols, traces of trinitro conpounds euid nitro-hydroxy carboxylic acids. The presence of individual compounds wais confirmed by comparison with the absorption spectrum of the pure compounds euid by thin-layer chromotography. Quantitative cuialyses of the concentrations of several components of the by-products were made. If a component did not have an absorption bcuid free from interference by euiother constituent of the mixture, queuititative cUialysis could still be achieved by mectsurement of the extinction coefficients of the interfering components at severcLL different frequencies, together with the absorbance of the mixture at these frequencies. Characteristic absorption bands used are shown in Tetble I. 

Table Hi Analysis of Pork Urine, Liver and Muscle Tissues for Sulfamethazine Residues by the EZ-Screen Test, Thin-Layer Chromotography (TIC) or the Sulpha-on-Site (SOS) Procedures...

Scott, P.M., Lawrence, J.W., and W. VanWalbeck, (1970). Detection of mycotoxins by thin-layer chromotography Application to screening for fungal extracts. Appl. Microbiol. 20, 839-842. 

Q DCM = Oichloromethartfl Extract in Control Urine n DCM DlcWoromethene Extract In Buffer FC -Fiaeh Chromatography TL - Thin Layer Chrometography HP " High Performance Liquid Chromotography... 

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