Alumina column chromatography

The reaction of the first-generation dendron 29 with the core, which is a trin-uclear platinum complex (30) bridged by 1,3,5-triethynylmesitylene, in a molar ratio of 3 1 resulted in the formation of the first-generation dendrimer (31). Since the reaction proceeded quantitatively and no side products were observed, the first-generation dendrimer was easily isolated by alumina column chromatography. 

Alumina column chromatography (rice grain, rice straw and soil)... 

Fish Polytron (methanol) or ball mill (hexane) extraction clean-up by GPC and alumina column chromatography GC/NPD 0.01 pg/g 79-97 Muiret al. 1981... 

Saponify (ambient), extract un-saponifiables with petroleum ether. Coprecipitate sterols with digitonin. Extract with petroleum ether. Alumina-column chromatography. 

As in preceding entry, but with alumina-column chromatography before semipreparative HPLC. 

Saponify (hot), extract unsaponifiables with hexane/CH2Cl2, 85 15. Alumina-column chromatography to obtain a vitamin D fraction and a 25(OH)D fraction. 

Digest sample with lipase, extract with pentane. Alumina-column chromatography. 

Treatment of the l-benzyl-2-benzotelluropyrylium salts 55 with base, or even upon alumina column chromatography, leads to deprotonation affording the corresponding exocyclic (Z)-olefin 56 quantitatively (Equation 19)... 

The cleanup steps described failed to remove a trace of impurity that accompanied heptachlor, DDE, and aldrin in the alumina column chromatography. This impurity later appeared in infrared spectra obtained from small samples of these insecticides. 

The same authors reported that TCPM was unstable during a sulfuric acid treatment and that TCPM could not be separated from the lipids by alumina column chromatography [8]. 

Alumina column chromatography has been a common cleanup method in PCDD/PCDF analyses [111, 112], Activated basic aluminum oxide has been used to isolate PCDEs from PCDDs and PCDFs [37, 43, 67], as well as from PCBs [120]. 

Metcalfe-Smith et al. [23] extracted PCAs with DCM and employed the same alumina column chromatography cleanup step as did Murray et al. [24], Using this method, PCA recoveries were reported to be greater than 90% [23], These authors did not encounter problems with degradation of PCAs on alumina as reported by Reiger and Ballschmiter [43]. 

Sample preparation Water was extracted with hexane for chlorpyrifos (a) and benzene for 3,5,6-trichloro-2-pyridinol (TCP) (b) banana samples were prepared using standard Food and Drug Administration procedures based on extraction, solvent partitioning, and silica gel or alumina column chromatography. 

One glass column for alumina column chromatography, 30-mm inner... 

The extract was subjected to silica gel and alumina column chromatography to give fractions containing anacardic acid, bilobol and cardanol. Further purification with an ODS column furnished anacardic... 

A mixture of 1.0 g p-methoxy-A -nitro-Af-methylaniline, 50 mL methanol, and 50 mL cone. HCl was refluxed for 2 h and then allowed to stand for 20 h at 25°C. The solution was cooled to 0°C, and the solid product was collected by suction filtration. The solid was purified by neutral alumina column chromatography using benzene as the eluent to afford 85% 2-nitro-4-methoxyl-A -methylaniline, m.p. 98-99°C. 

A mixture of 1.13 g orf/to-isonitrile phenyl trimethylsilyl acetylene (5.68 mmol), 2.10 ethanethiol (28.4 mmol), 0.14 g AIBN (0.85 mmol), and 142.0 mL toluene was refluxed for 15 min and then concentrated in vacuo. The residue was purified by alumina column chromatography using hexanes/EtOAc (10 1) as the eluent to afford 1.57 g 2-ethylthio-3-(l-trimethylsilyl-l -ethylthio)methyl indole as a pale yellow solid, in a yield of 86%, m.p. 94-96°C. 

Thus alumina column chromatography was used< > for the separation of caroten from chlorophyll in the determination of the former based on the reaction with iodine (cf. p. 131). Carotene is eluted from the alumina column with a petroleum ether-benzene mixture, whereas chlorophyll and other carotenoids remain on the column. 

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