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Nucleophilic displacement reactions of 5'-derivatised nucleosides in a vibration ball mill.

ABSTRACT: Vibration ball-milling in a zirconia-lined vessel afforded clean and quantitative nucleophilic displacement reactions between 4-methoxybenzylthiolate salts and nucleoside 5'-halides or 5'-tosylates in five to 60 minutes. Under these conditions, commonly-encountered nucleoside cyclisation byproducts (especially of purine nucleosides) were not observed. Liquid-assisted grinding of the same 5'-iodide and 5'-tosylate substrates with potassium selenocyanate in the presence of DMF produced the corresponding 5'-selenocyanates in variable yields over the course of between one and eleven hours thereby avoiding the preparation and use of hygroscopic tetrabutylammonium salts.

SUBMITTER: Eguaogie O

PROVIDER: S-EPMC5238552 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Nucleophilic displacement reactions of 5'-derivatised nucleosides in a vibration ball mill.

Eguaogie Olga O Conlon Patrick F PF Ravalico Francesco F Sweet Jamie S T JS Elder Thomas B TB Conway Louis P LP Lennon Marc E ME Hodgson David R W DR Vyle Joseph S JS

Beilstein journal of organic chemistry 20170113

Vibration ball-milling in a zirconia-lined vessel afforded clean and quantitative nucleophilic displacement reactions between 4-methoxybenzylthiolate salts and nucleoside 5'-halides or 5'-tosylates in five to 60 minutes. Under these conditions, commonly-encountered nucleoside cyclisation byproducts (especially of purine nucleosides) were not observed. Liquid-assisted grinding of the same 5'-iodide and 5'-tosylate substrates with potassium selenocyanate in the presence of DMF produced the corresp ...[more]

PMID: 28179952

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