{"created":"2023-05-15T14:53:01.238387+00:00","id":72337,"links":{},"metadata":{"_buckets":{"deposit":"4773f68f-3b98-4741-b4ab-682b12aaa6e7"},"_deposit":{"created_by":1,"id":"72337","owners":[1],"pid":{"revision_id":0,"type":"depid","value":"72337"},"status":"published"},"_oai":{"id":"oai:repo.qst.go.jp:00072337","sets":["10:28"]},"author_link":["712448","712451","712450","712447","712449"],"item_10005_date_7":{"attribute_name":"発表年月日","attribute_value_mlt":[{"subitem_date_issued_datetime":"2017-05-16","subitem_date_issued_type":"Issued"}]},"item_10005_description_5":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"Introduction. [11C]Cyanide has been used as a useful intermediate for incorporation of 11C-labelled functional groups such as 11COOH, 11CONH2 and 11CH2NH2 into PET probes. [11C]Cyanide is generally prepared by heating [11C]CH4 under NH3 gas flow at more than 900°C in a column filled with platinum. The traditional method, however, requires an additional system for [11C]cyanide production. In this study, we explored a facile method to prepare [11C]cyanide without any special equipment, reagents and conditions. Hooker et al. reported that [11C]HCHO is readily prepared with Me3NO from [11C]MeI in DMF.[1] Augustine et al. reported that alkyl- and aryl-aldehydes can be efficiently converted to corresponding nitriles using NH2OH‧HCl in DMSO.[2] Based on these reports, we investigated the applicability of Augustine’s reaction to [11C]cyanide preparation from [11C]MeI which is commonly used for 11C-labelling.\nMethods. To a 50 μL of [11C]MeI solution in DMF or DMSO (30–50 MBq), a 50 μL of saturated Me3NO (<2 mg) in DMSO was added. Saturated NH2OH‧HCl solution in DMSO (<10 mg, 100μL) was subsequently added to the reaction mixture. To investigate the effect of HCl addition, 10 μL of 4M HCl/dioxane was added immediately or 2 min after the addition of NH2OH‧HCl. The reaction conditions are summarized in Table 1. Radiochemical yields (average of n=2) were determined by radio-HPLC analysis of the reaction solution.\nResults. In all reactions, [11C]MeI and [11C]HCHO were almost completely consumed, and [11C]H2CNOH and [11C]cyanide were observed as the major products at the end of reaction. The addition of HCl enhanced dehydration of [11C]H2CNOH to form [11C]cyanide (Entry 1, 3). The timing of HCl addition was important to obtain good yields of [11C]cyanide (Entry 3, 5). Efficient dehydration required heating at >90°C (Entry 2–5). Based on these results, [11C]MeI, NH2OH‧HCl and HCl were serially mixed in a DMSO solution of Me3NO and reacted at 90°C (Entry 6, 7). Despite a report indicating that DMSO is not a suitable solvent for [11C]HCHO preparation from [11C]MeI,[1] we performed a DMF-free [11C]cyanide preparation experiment. This produced [11C]cyanide in 81% radiochemical yield after 10 min reaction time.\nConclusion. We have developed a facile method for efficient [11C]cyanide preparation using conventional lab-ware. Further optimization of reaction conditions and the application of the [11C]cyanide prepared with this method are in progress.\n\\n[1] J. M. Hooker, Matthias Schönberger, H. Schieferstein, J. S. Fowler, Angew. Chem. Int. Ed. 2008, 47, 5989–5992.\n[2] J. K. Augustine, A. Bombrun, R. N. Atta, Synlett, 2011, 15, 2223–2227. \nIntroduction. [11C]Cyanide has been used as a useful intermediate for incorporation of 11C-labelled functional groups such as 11COOH, 11CONH2 and 11CH2NH2 into PET probes. [11C]Cyanide is generally prepared by heating [11C]CH4 under NH3 gas flow at more than 900°C in a column filled with platinum. The traditional method, however, requires an additional system for [11C]cyanide production. In this study, we explored a facile method to prepare [11C]cyanide without any special equipment, reagents and conditions. Hooker et al. reported that [11C]HCHO is readily prepared with Me3NO from [11C]MeI in DMF.[1] Augustine et al. reported that alkyl- and aryl-aldehydes can be efficiently converted to corresponding nitriles using NH2OH‧HCl in DMSO.[2] Based on these reports, we investigated the applicability of Augustine’s reaction to [11C]cyanide preparation from [11C]MeI which is commonly used for 11C-labelling.\nMethods. To a 50 μL of [11C]MeI solution in DMF or DMSO (30–50 MBq), a 50 μL of saturated Me3NO (<2 mg) in DMSO was added. Saturated NH2OH‧HCl solution in DMSO (<10 mg, 100μL) was subsequently added to the reaction mixture. To investigate the effect of HCl addition, 10 μL of 4M HCl/dioxane was added immediately or 2 min after the addition of NH2OH‧HCl. The reaction conditions are summarized in Table 1. Radiochemical yields (average of n=2) were determined by radio-HPLC analysis of the reaction solution.\nResults. In all reactions, [11C]MeI and [11C]HCHO were almost completely consumed, and [11C]H2CNOH and [11C]cyanide were observed as the major products at the end of reaction. The addition of HCl enhanced dehydration of [11C]H2CNOH to form [11C]cyanide (Entry 1, 3). The timing of HCl addition was important to obtain good yields of [11C]cyanide (Entry 3, 5). Efficient dehydration required heating at >90°C (Entry 2–5). Based on these results, [11C]MeI, NH2OH‧HCl and HCl were serially mixed in a DMSO solution of Me3NO and reacted at 90°C (Entry 6, 7). Despite a report indicating that DMSO is not a suitable solvent for [11C]HCHO preparation from [11C]MeI,[1] we performed a DMF-free [11C]cyanide preparation experiment. This produced [11C]cyanide in 81% radiochemical yield after 10 min reaction time.\nConclusion. We have developed a facile method for efficient [11C]cyanide preparation using conventional lab-ware. Further optimization of reaction conditions and the application of the [11C]cyanide prepared with this method are in progress.\n\\n[1] J. M. Hooker, Matthias Schönberger, H. Schieferstein, J. S. Fowler, Angew. Chem. Int. Ed. 2008, 47, 5989–5992.\n[2] J. K. Augustine, A. Bombrun, R. N. Atta, Synlett, 2011, 15, 2223–2227.","subitem_description_type":"Abstract"}]},"item_10005_description_6":{"attribute_name":"会議概要（会議名, 開催地, 会期, 主催者等）","attribute_value_mlt":[{"subitem_description":"22nd International symposium on radiopharmaceutical science ","subitem_description_type":"Other"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"metadata only access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_14cb"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"Kikuchi, Tatsuya"}],"nameIdentifiers":[{"nameIdentifier":"712447","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Zhang, Ming-Rong"}],"nameIdentifiers":[{"nameIdentifier":"712448","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"D., Gee Antony"}],"nameIdentifiers":[{"nameIdentifier":"712449","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"菊池 達矢","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"712450","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"張 明栄","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"712451","nameIdentifierScheme":"WEKO"}]}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"conference object","resourceuri":"http://purl.org/coar/resource_type/c_c94f"}]},"item_title":"A preliminary study of facile [11C]cyanide preparation from [11C]methyl iodide ","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"A preliminary study of facile [11C]cyanide preparation from [11C]methyl iodide "}]},"item_type_id":"10005","owner":"1","path":["28"],"pubdate":{"attribute_name":"公開日","attribute_value":"2017-05-25"},"publish_date":"2017-05-25","publish_status":"0","recid":"72337","relation_version_is_last":true,"title":["A preliminary study of facile [11C]cyanide preparation from [11C]methyl iodide "],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2023-05-15T19:41:01.624204+00:00"}