Ni-Catalyzed Synthesis of Dienes

Under optimized conditions (MeCN, 40 °C, 5h, 3 mol% Ni(acac)2, 30 mol% PPhCy2) the synthetic procedure was carried out with good yields and the asymmetric dienes were isolated in pure form using flash-chromatography  

According to solution phase NMR analysis and solid state X-ray analysis, the structures possess s auche configuration of the central C—C bond in contrast to the s-trans configuration reported for the majority of known 1,3-dienes. This is the first 

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