51233-65-9Relevant academic research and scientific papers
Lewis-base-catalysed selective reductions of ynones with a mild hydride donor
Sch?mberg,Zi,Vilotijevic
, p. 3266 - 3269 (2018/04/05)
Ynones are efficiently reduced with a mild hydride donor in the presence of a catalytic amount of nucleophilic phosphines. The reactions are selective 1,2-reductions that give propargyl alcohols in yields of up to 96%. It is proposed that success in these reactions depends on the activation of ynones by a Lewis base catalyst. A protic additive plays a key role in suppressing the undesired reaction pathways and accelerating the 1,2-reductions.
Trans -Hydroboration vs. 1,2-reduction: Divergent reactivity of ynones and ynoates in Lewis-base-catalyzed reactions with pinacolborane
Zi, You,Sch?mberg, Fritz,Seifert, Fabian,G?rls, Helmar,Vilotijevic, Ivan
supporting information, p. 6341 - 6349 (2018/09/10)
Ynones and ynoates react with pinacolborane in a divergent manner in the presence of nucleophilic phosphine catalysts. Ynones are transformed to the corresponding propargyl alcohols in good yields with high regio- and chemoselectivity. Ynoates undergo highly regio- and stereoselective trans-hydroboration to produce E-vinylboronates. Impressive divergence in reactivity of ynones and ynoates can be traced back to the mechanistic aspects of 1,2-reduction and trans-hydroboration. A comparative analysis of the two pathways paints a complex picture in which different reaction rates control selectivity in these seemingly unrelated processes and explains how sufficiently acidic protons in the reaction mixtures can be used to steer the selectivity in different directions.
