306281-84-5Relevant academic research and scientific papers
Asymmetric Allylic C-H Alkylation via Palladium(II)/ cis-ArSOX Catalysis
Liu, Wei,Ali, Siraj Z.,Ammann, Stephen E.,White, M. Christina
, p. 10658 - 10662 (2018/09/06)
We report the development of Pd(II)/cis-aryl sulfoxide-oxazoline (cis-ArSOX) catalysts for asymmetric C-H alkylation of terminal olefins with a variety of synthetically versatile nucleophiles. The modular, tunable, and oxidatively stable ArSOX scaffold is key to the unprecedented broad scope and high enantioselectivity (37 examples, avg. > 90% ee). Pd(II)/cis-ArSOX is unique in its ability to effect high reactivity and catalyst-controlled diastereoselectivity on the alkylation of aliphatic olefins. We anticipate that this new chiral ligand class will find use in other transition metal catalyzed processes that operate under oxidative conditions.
Enantioselective complexation of phenolic crown ethers with chiral aminoethanol derivatives: Effects of substituents of aromatic rings of hosts and guests on complexation
Hirose, Keiji,Ogasahara, Kazuko,Nishioka, Kazuyuki,Tobe, Yoshito,Naemura, Koichiro
, p. 1984 - 1993 (2007/10/03)
Optically active azophenolic crown ethers having phenyl groups substituted at the respective para-position were prepared and their association constants with chiral aminoethanol derivatives, including 2-amino-2-phenyl-ethanols having an electron-donating or an electron-withdrawing group, were determined in chloroform by means of UV-vis titration methods. The enantioselectivities of these crown ethers are estimated from the ratio of the association constants KR/KS and the effect of aromatic substituents of both hosts and guests on the binding abilities and enantioselectivities is discussed. The structures of the complexes were investigated on the basis of the 1H NMR and UV-vis spectra.
