Exploiting morph-DAST mediated ring-expansion of substituted cyclic β-amino alcohols for the preparation of cyclic fluorinated amino acids. Synthesis of 5-fluoromethylproline and 5-fluoropipecolic acid

The synthesis of proline analogues bearing a fluorine-containing substituent at the fifth position of the pyrrolidine ring, racemic trans- and cis-5-fluoromethyl prolines, was performed. The key step of the synthesis is a transformation of the CH₂OH-group into the CH₂F-one using morpholinosulfur trifluoride. During the synthesis, an efficient procedure to prepare trans- and cis-5-fluoropipecolic acids was elaborated.

Mykhailiuk P. K.; Shishkina S. V.; Shishkin O. V.; Zaporozhets O. A.; Komarov I. V.
Tetrahedron 2011, 67 (17), 3091-3097
DOI: 10.1016/j.tet.2011.02.082