Christian Chapuis and Robert Brauchli
In an article about different irones preparations
and analogues optically active,
Chapuis described the first enantioselective
synthesis of (-)-cis-g-Irone.
Reagents : a) Me3SI, DMSO, NaOH; b) SnCl4, toluene; c) Ph3P=CHCOCH3, toluene
Chapuis obtained a trans / cis mixture, only separable by preparative GC. |