Highly Diastereoselective Zn/SnCl<sub>2</sub>-Mediated <i>gem</i>-Difluoroallylation of Chiral Hydrazones
作者:Xuyi Yue、Xingang Zhang、Feng-Ling Qing
DOI:10.1021/ol802361p
日期:2009.1.1
gem-Difuoroallylic zinc reacts with chiral hydrazones 1 in the presence of SnCl2 to afford the versatile and chiral fluorinated building blocks, gem-difluorohomoallylic amines, In good yields and high diastereoselectivities.
Highly Diastereoselective Mannich-Type Reactions of Chiral <i>N</i>-Acylhydrazones
作者:Mikkel F. Jacobsen、Liviu Ionita、Troels Skrydstrup
DOI:10.1021/jo0358170
日期:2004.7.1
optimal reaction conditions entailed the simple use of ZnCl2 in acetonitrile at room temperature. Hydrazones derived from phenyl-, isopropyl-, and benzyl-substituted 2-oxazolidinones were examined in the reaction in terms of yield and diastereoselectivity. The facile SmI2-mediated N−N bond cleavage of the formed hydrazines was demonstrated yielding a β-amino acid derivative. Hence, the overall reaction