title: A simplified and improved synthesis of [11C]phosgene with iron and iron (III) oxide.
abstract: [11C]Phosgene ([11C]COCl2), a useful precursor for labeling several radiopharmaceuticals, is generally produced by catalytic oxidation of [11C]carbon tetrachloride over Fe granules, although in low yields or with poor reproducibility. In order to develop am improved synthesis of [11C]phosgene, two oxidizing agents, Fe2O3 and CuO, were examined. The yield of [11C]phosgene was significantly increased using Fe2O3 powder mixed with Fe granules, while the use of CuO alone, or CuO powder mixed with Fe granules resulted in an insignificant yield. The yield and specific activity of S- (-) [11C]CGP-12177 synthesized using Fe2O3 powder mixed with Fe granules were markedly higher than those synthesized by the previous methods using Fe granules alone or Fe granules mixed with Fe powder. Thus, in the present study, we developed a simple and practical method for the synthesis of [11C]phosgene, which provided an improved yield of S- (-) [11C]CGP-12177.
authors.affiliation: Department of Tracer Kinetics, Graduate School of Medicine, Hokkaido University, Kita 15 Nishi 7, Kita-ku, 060-8638, Sapporo, Japan.
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Nishijima
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kuge
authors.forename: Koh-ichi
authors.initials: K
authors.lastname: Seki
authors.forename: Kazue
authors.initials: K
authors.lastname: Ohkura
authors.forename: Noriko
authors.initials: N
authors.lastname: Motoki
authors.forename: Kotaro
authors.initials: K
authors.lastname: Nagatsu
authors.forename: Akira
authors.initials: A
authors.lastname: Tanaka
authors.forename: Eriko
authors.initials: E
authors.lastname: Tsukamoto
authors.forename: Nagara
authors.initials: N
authors.lastname: Tamaki
mesh_terms: D002224:Carbanilides / Q000138:chemical synthesis; D002250:Carbon Radioisotopes; D002251:Carbon Tetrachloride / Q000138:chemical synthesis; D003300:Copper / Q000737:chemistry; D005296:Ferrous Compounds / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D007553:Isotope Labeling; D010705:Phosgene / Q000138:chemical synthesis* / Q000737:chemistry; D011412:Propanolamines / Q000138:chemical synthesis; D019275:Radiopharmaceuticals / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D002224:Carbanilides; D002250:Carbon Radioisotopes; D005296:Ferrous Compounds; D011412:Propanolamines; D019275:Radiopharmaceuticals; D010705:Phosgene; D003300:Copper; D002251:Carbon Tetrachloride; D007501:Iron; C034236:ferrous oxide; C033394:CGP 12177; C030973:cupric oxide