2018

Journal of Organic Chemistry

Rocznik: 2018 | Tom: 83 | Numer: 10

artykuł naukowy

angielski

EN Mechanistic and stereochemical aspects of the reaction of boranephosphonate diesters with amines promoted by iodine were investigated. This is a complex, multistep reaction that ultimately produces the corresponding phosphoramidate diesters via a formal replacement of the borane group by an amine moiety. We found by a stereochemical correlation iodine that, contrary to a literature report, the whole transformation proceeded with total inversion of the configuration at the phosphorus center. Our study also showed that instead of the postulated nudeophilic substitution by iodide at the phosphorus center of the initially formed intermediate, the corresponding iodoboranephosphonate, the crucial step of the reaction involved intermediacy of H-phosphonate derivatives that reacted with iodine to afford ultimately phosphoramidate diesters. The reaction of the iodoboranephosphonate with the amine to produce an aminoboranephosphonate diester that rapidly dissociated into the corresponding H-phosphonate and the borane parts was apparently instrumental to the formation of an H-phosphonate diester intermediate.

5496 - 5505

10.1021/acs.joc.8b00419

https://pubs.acs.org/doi/10.1021/acs.joc.8b00419

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