Synthesis and Application of Substituted 1,16-Dihydroxytetraphenylenes in Catalytic Asymmetric Allylboration of Ketones
作者:Guo-Li Chai、Bo Zhu、Junbiao Chang
DOI:10.1021/acs.joc.8b02475
日期:2019.1.4
The synthesis and application of a newly designed C2-symmetric chiral-substituted 1,16-dihedroxytetraphenylene (DHTP) is reported. Efficient syntheses of enantiopure substituted DHTP were accomplished, and these enantiopure compounds were used as organocatalysts in asymmetric allylboration of ketones under very mild conditions. Accordingly, several tertiary alcohols were generated in moderate to good
A new class of chiral spirocyclic borate ligands 5a–d with a rigid borocycle has been developed. The catalyst formed from chromium(II)-5a promotes the highly efficient enantioselective Nozaki–Hiyama allylation of alkyl and aryl ketones using allyl bromide. The scope of the present method is shown to be wide, and it affords an efficient access to chiral tertiary homoallylic alcohols.
A Chiral Bipyridyl Alcohol for Catalytic Enantioselective Nozaki-Hiyama-Kishi Allylation of Aldehydes and Ketones
作者:Rui-Yu Chen、Attrimuni P. Dhondge、Gene-Hsian Lee、Chinpiao Chen
DOI:10.1002/adsc.201400945
日期:2015.3.23
Nozaki–Hiyama–Kishi (NHK) allylation of aldehydes and ketones with allylic halides. The allylation of various aromatic, α,β‐unsaturated, and aliphatic aldehydes and ketones produces the desired homoallylic alcohols in satisfactory yields (up to 98%) and high enantioselectivities (up to 99% ee). The present method can be applied widely and affords an efficient means of obtaining chiral homoallylic alcohols.