Mechanism of hydrogen atom transfer in the photolytic rearrangement of N-bromophenylalaninamide derivatives

Christopher J. Easton*, Martin C. Merrett, Pasquale Razzino

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    2 Citations (Scopus)

    Abstract

    Photolysis of N-bromo-N-tert-butyl-Na-phthaloylphenylalaninamide gave a 1:1 mixture of the diastereomers of 3-bromo-N-tert-butyl-Na-phthaloylphenylalaninamide. Reactions carried out with various concentrations of the N-bromoamide, and in the presence of 4-tert-butyltoluene, showed that the ratio of the product bromophenylalanine derivatives to 4-tert-butylbenzyl bromide varied as a function of the concentration of the N-bromoamide, indicating that the bromophenylalanine derivatives are formed through an intermolecular process and not by intramolecular 1,4-hydrogen atom transfer of the corresponding amidyl radical. Results of reactions of N-bromo-N-tert-butyl-Na-phthaloyl-p-methylphenylalaninamide are also consistent with this interpretation. Reactions of stereoselectively β-deuteriated derivatives of N-bromo-N-tert-butyl-Na-phthaloylphenylalaninamide established that the pro-S benzylic hydrogen of the phenylalaninamide is selectively abstracted, by a factor of ca. 3.8, in this intermolecular process.

    Original languageEnglish
    Pages (from-to)693-697
    Number of pages5
    JournalJournal of the Chemical Society. Perkin Transactions 2
    Issue number4
    DOIs
    Publication statusPublished - Apr 2000

    Fingerprint

    Dive into the research topics of 'Mechanism of hydrogen atom transfer in the photolytic rearrangement of N-bromophenylalaninamide derivatives'. Together they form a unique fingerprint.

    Cite this