Palladium-Catalyzed Preparation of Vinylallenes from 2-Bromo-1,3,5-trienes via an Alkylidene-π-allylpalladium-Mediated Formal SN2‘ ‘ Pathway
摘要:
[GRAPHICS]A novel Pd-catalyzed reaction to prepare conjugated vinylallenes from 2-bromo-1,3,5-triene and a soft nucleophile via a formal S(N)2" pathway was developed. The reaction proceeds via alkylidene-d-allylpalladium and allenyl-d-allylpalladium intermediates, and a dynamic process involving the two palladium intermediates played important roles in determining the selectivity of the Pd-catalyzed reaction. The reaction was extended to an asymmetric counterpart, and an axially chiral vinylallene was obtained with up to 81% ee.
Palladium-Catalyzed Preparation of Vinylallenes from 2-Bromo-1,3,5-trienes via an Alkylidene-π-allylpalladium-Mediated Formal SN2‘ ‘ Pathway
摘要:
[GRAPHICS]A novel Pd-catalyzed reaction to prepare conjugated vinylallenes from 2-bromo-1,3,5-triene and a soft nucleophile via a formal S(N)2" pathway was developed. The reaction proceeds via alkylidene-d-allylpalladium and allenyl-d-allylpalladium intermediates, and a dynamic process involving the two palladium intermediates played important roles in determining the selectivity of the Pd-catalyzed reaction. The reaction was extended to an asymmetric counterpart, and an axially chiral vinylallene was obtained with up to 81% ee.
Palladium-Catalyzed Preparation of Vinylallenes from 2-Bromo-1,3,5-trienes via an Alkylidene-π-allylpalladium-Mediated Formal S<sub>N</sub>2‘ ‘ Pathway
[GRAPHICS]A novel Pd-catalyzed reaction to prepare conjugated vinylallenes from 2-bromo-1,3,5-triene and a soft nucleophile via a formal S(N)2" pathway was developed. The reaction proceeds via alkylidene-d-allylpalladium and allenyl-d-allylpalladium intermediates, and a dynamic process involving the two palladium intermediates played important roles in determining the selectivity of the Pd-catalyzed reaction. The reaction was extended to an asymmetric counterpart, and an axially chiral vinylallene was obtained with up to 81% ee.