Asymmetric Alkenylation of Enonesand Other α,β-Unsaturated Carbonyl DerivativesUsing Chiral 3,3′-Disubstituted Binaphthols and Boronates

asymmetric conjugate addition;enones;alkenylboronates;α,β-unsaturated carbonyl compounds;Chemistry

Guobadia, Bobby

University of Waterloo

关键词: asymmetric conjugate addition;    enones;    alkenylboronates;    α,β-unsaturated carbonyl compounds;    Chemistry;   

Others  :  https://uwspace.uwaterloo.ca/bitstream/10012/4455/1/Bobby_Guobadia.pdf

瑞士|英语

来源: UWSPACE Waterloo Institutional Repository

【 摘 要 】

Various α,β-unsaturated carbonyl compounds and derivatives were explored in order to expand the range of substrates for the 1,4-addition of alkenylboronates using3,3′-disubstituted binaphthols. Enones 2.60 were examined and found to be suitable for conjugate addition under our proposed reaction conditions.The asymmetric 1,4-additions of alkenylboronates to enones 2.60 using catalytic amounts of 3,3′-disubstituted binaphthols was shown to occur with moderate to good yields and high enantioselectivities. The chiral products could serve as enantioenriched substrates for further transformation such as asymmetric reduction, which was performed with good yield and selectivity. The absolute configuration for the alkenylation of enones was also confirmed to be the (R) enantiomer using (S)-3,3′-disubstituted binaphthols via X-ray crystallographic analysis.Investigations into selective Baeyer-Villiger oxidation of 1,4-addition productsof enones was also examined. Although the desire ester products were not obtained, intriguing informative findings were still obtained from the investigation.