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E E Pullen

Publications and source records attributed to E E Pullen.

4 recordsLinked to original sources
PubMed2001

Development of an automated in-line microfiltration system coupled to an HPLC for the determination of solubility.

An automated in-line microfiltration system coupled to an HPLC was developed for the determination of solubility. Filtrations and subsequent solubility determinations are performed using a standard Gilson dilutor and autosampler and dual Rheodyne valves equipped with a filtration assembly and configured to an HPLC system. The solubility data obtained using the automated in-line microfiltration system are in good agreement with the results obtained using conventional manual preparation techniques. Automating this labor-intensive and often variable portion of the solubility determination provides a reliable means of improving both the consistency and quality of solubility data.

Chromatography, High Pressure Liquid↗
PubMed2000

Syntheses and structures of methyltris(pyrazolyl)silane complexes of the group 6 metals.

The methyltris(3,5-dimethylpyrazolyl)silane ligand, TpsMe2, was readily prepared by the metathesis reaction of methyltrichlorosilane with 3 equiv of lithium 3,5-dimethylpyrazolate. The octahedral tricarbonyl complexes (TpsMe2)M(CO)3 were synthesized either by ligand exchange with the labile nitrile adducts M(CO)3(NCR)3 (M = Cr, Mo, R = Me; M = W, R = Et) or thermally by direct substitution on the hexacarbonyls M(CO)6 (M = Cr, Mo). The three new complexes were characterized by a combination of analytical and spectroscopic techniques, including electrospray ionization mass spectrometry and single-crystal X-ray diffraction. They are all isostructural and display in the solid state the expected distorted octahedral geometries with facially coordinated tris(pyrazolyl)silane ligands. Crystallographic data were used to calculate the ligand cone angles (251-264 degrees) in (TpsMe2)M(CO)3 and also to estimate a value of 1.59 A for the covalent radius of octahedral W(0).

Journal Article↗