Synthesis of Chiral Tertiary Allylic- and Propargylic Fluorides from Nonaflates of Chiral α-Fluorinated β-Keto Dicarbonyl Compounds

The acetyl group of chiral α-fluorinated dicarbonyl compounds was transformed to nonaflates through a reaction with perfluorobutanesulfonyl fluoride in the presence of DBU in 82-95% yield. These nonaflates were used in Suzuki and Sonogashira coupling reactions to afford chiral tertiary allylic fluorides bearing gem-disubstituted terminal alkenes with excellent optical purities (45-91%, ≥94% ee). In addition, chiral tertiary propargylic fluorides were obtained from the reaction of nonaflates with DBU (73-86%, ≥94% ee).

Dienylation of N-benzoylhydrazones with CF3-substituted homoallenylboronates in water

A convenient method for the dienylation of N-benzoylhydrazones in water has been developed. This protocol expanded the synthetic application of functionalized homoallenylboronates to provide the useful 2-aminomethyl-1,3-diene derivatives with high efficiency (up to 99% yield) and stereoselectivity without using any catalyst, additive or inert atmosphere. Furthermore, the transformation of a 2-aminomethyl-1,3-diene derivative to synthesize a functionalized pyrrolidine derivative was also explored.