Synthesis of Vicinal Dimethyl Chirons by Asymmetric Hydrogenation of Trisubstituted Alkenes
摘要:
Roche ester derivatives were converted to trisubstituted alkenes with allylic chiral centers. Hydrogenation of these substrates with chiral analogues of Crabtree's catalyst, specifically, an optically active carbene oxazoline derivative, were found to be mostly catalyst controlled. However, the peripheral functionalities and protecting groups had significant effects and could be adjusted to give high stereoselectivities. The upshot of this work is that alpha,omega-functionalized chirons to introduce 1,2-dimethyl functionalities into acyclic chains have been developed.
Synthesis of Vicinal Dimethyl Chirons by Asymmetric Hydrogenation of Trisubstituted Alkenes
摘要:
Roche ester derivatives were converted to trisubstituted alkenes with allylic chiral centers. Hydrogenation of these substrates with chiral analogues of Crabtree's catalyst, specifically, an optically active carbene oxazoline derivative, were found to be mostly catalyst controlled. However, the peripheral functionalities and protecting groups had significant effects and could be adjusted to give high stereoselectivities. The upshot of this work is that alpha,omega-functionalized chirons to introduce 1,2-dimethyl functionalities into acyclic chains have been developed.
Synthesis of Vicinal Dimethyl Chirons by Asymmetric Hydrogenation of Trisubstituted Alkenes
作者:Jian Zhao、Kevin Burgess
DOI:10.1021/ja905458n
日期:2009.9.23
Roche ester derivatives were converted to trisubstituted alkenes with allylic chiral centers. Hydrogenation of these substrates with chiral analogues of Crabtree's catalyst, specifically, an optically active carbene oxazoline derivative, were found to be mostly catalyst controlled. However, the peripheral functionalities and protecting groups had significant effects and could be adjusted to give high stereoselectivities. The upshot of this work is that alpha,omega-functionalized chirons to introduce 1,2-dimethyl functionalities into acyclic chains have been developed.