Ulbrich Dirk, Daniliuc Constantin G, Haufe Günter
Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstraße 40, D-48149 Münster, Germany.
Org Biomol Chem. 2016 Mar 7;14(9):2755-67. doi: 10.1039/c6ob00131a.
Intending to synthesize ω,ω-difluoroalkyl amino acid derivatives by oxidative desulfurization-fluorination reactions of suitable arylthio-2-phthalimido butanoates and pentanoates, in addition to small amounts of the target products, mainly α,ω-polyfluorinated amino acid derivatives were formed by additional sulfur-assisted α-fluorination. This novel structural motif was verified spectroscopically as well as by X-ray analysis. A plausible mechanism of formation is suggested. Using a different approach, δ,δ-difluoronorvaline hydrochloride was synthesized with at least 36% enantiomeric excess via deoxofluorination of the corresponding aldehyde.
为了通过合适的芳硫基-2-邻苯二甲酰亚胺丁酸酯和戊酸酯的氧化脱硫-氟化反应合成ω,ω-二氟烷基氨基酸衍生物，除了少量目标产物外，主要通过额外的硫辅助α-氟化形成了α,ω-多氟氨基酸衍生物。这种新颖的结构基序通过光谱以及X射线分析得到了验证。提出了一种合理的形成机理。采用不同的方法，通过相应醛的脱氧氟化反应合成了对映体过量至少为36%的δ,δ-二氟正缬氨酸盐酸盐。
