A variety of acyclic chiral dienes were synthesized in a single step via palladium(0)-catalyzed asymmetric allylic and homoallylic C À H di-A C H T U N G T R E N N U N G amination of terminal olefins. The applications of such simple dienes as steering ligands for rhodi-A C H T U N G T R E N N U N G um(I)-catalyzed asymmetric 1,4-additions afforded the corresponding adducts in excellent yields and up to 85% ee.Keywords: acyclic chiral dienes; asymmetric catalysis; asymmetric diamination; conjugated addition; diene ligands Chiral olefins have proven to be excellent steering ligands for asymmetric catalysis, and some of them even exhibit a distinct advantage over other types of ligands to afford higher reactivities and/or enantioselectivities. [1,2] With lots of effort devoted to this lately emerging area, a few fantastic chiral chelating diene ligands bearing bicyclic frameworks have been successfully developed. [3][4][5][6] The bicyclic structures of these ligands play a crucial role in the asymmetric reactions, but also partially result in some difficulties in ligand synthesis. Hence, exploring novel, effective, and accessible chiral dienes is still one of the most important subjects in this field.[2b] Inspired by the fact that 1,5-hexadiene (1) has an ability to act as a steering ligand, very recently, we reported that a simple chiral acyclic diene 2 (Scheme 1) can be employed as an effective ligand for promoting Rh(I)-catalyzed asymmetric 1,4-additons with encouraging yields and ees (Scheme 2), [7,8] which demonstrates that the complexes formed between Rh and a flexible diene are stable enough to ensure asymmetric induction.[9] Because of the convenient synthesis, chiral acyclic dienes have the potential to become a class of promising ligands in the future. Herein, we wish to report our efforts on this subject.In our previous work, when two hydroxy groups were introduced into the achiral 1,5-hexadiene skeleton, a simple chiral chain diene ligand 2 was successfully achieved, which suggests that other types of chiral dienes containing 1,5-hexadiene skeletons are also candidate ligands. We envisioned that introduction of imidazolidin-2-one backbones to 1,5-hexadiene may provide a good opportunity to develop novel diene ligands (3) for asymmetric catalysis (Scheme 1).[10] The combination of flexible terminal olefins and rigid imidazolidin-2-one frameworks in ligand 3 and how it might affect asymmetric induction is interesting. Therefore, building the chiral imidazolidin-2-one frameworks became one of the key points.

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A kinetic resolution of hindered Morita-Baylis-Hillman adducts has been successfully achieved in excellent selectivities via Rh(I)-catalyzed asymmetric 1,4-addition/β-hydroxyelimination with the use of a chiral sulfinamide/olefin hybrid ligand. This study provides a novel and efficient access to both optically active hindered highly functionalized alkenes and Morita-Baylis-Hillman adducts.