ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTApparatus and materials for hyperpressure gas chromatography of nonvolatile compoundsNicholas M. Karayannis, Alsoph H. Corwin, Earl W. Baker, Ernst. Klesper, and Joseph A. WalterCite this: Anal. Chem. 1968, 40, 11, 1736–1739Publication Date (Print):September 1, 1968Publication History Published online1 May 2002Published inissue 1 September 1968https://pubs.acs.org/doi/10.1021/ac60267a035https://doi.org/10.1021/ac60267a035research-articleACS PublicationsRequest reuse permissionsArticle Views124Altmetric-Citations45LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

Under mild alkaline conditions hemin can be catalytically hydrogenated to the iron complex of mesoporphyrin IX. Subsequent demetallation yields mesoporphyrin IX. In this way pure mesoporphyrin IX becomes readily accessible. In contrast, the mesoporphyrin produced from hemin by formic acid reduction has been shown by partition chromatography to be a mixture rather than a pure compound. Mesoporphyrin IX can be converted to pure etioporphyrin III in 20% yield by a seven-step reaction series including the Curtius rearrangement, Hofmann degradation, and catalytic hydrogenation.

A number of porphyrins can be resolved by column partition chromatography using dimethyl sulfoxide on a silica support and cyclohexane as the mobile phase. This partition system was used as a criterion of success in the selection of new methods for the synthesis of porphyrins. The important factors which allow quantitative and reproducible evaluations of Rf values are noted, and differences in dielectric constant are recommended as a useful test for selection of other suitable chromatographic solvent pairs.