<i>trans</i>-Hydroboration of Propiolamides: Access to Primary and Secondary (<i>E</i>)-β-Borylacrylamides
作者:R. Justin Grams、Russell G. Fritzemeier、Carla Slebodnick、Webster L. Santos
DOI:10.1021/acs.orglett.9b02408
日期:2019.9.6
A base-mediated trans-hydroboration of propiolamides that provides access to previously elusive primary and secondary (E)-β-borylacrylamide products has been developed. In the presence of n-butyllithium and pinacolborane, complete regioselectivity and stereoselectivity is observed, affording the corresponding vinylboronate products in up to 91% yield. A wide variety of primary and secondary amides
Brønsted Base‐Mediated Regio‐ and Stereoselective
<i>trans‐</i>
Silaboration of Propargylamides: Access to 1,2‐Vinylborasilanes
作者:Russell Fritzemeier、Webster L. Santos
DOI:10.1002/chem.201703774
日期:2017.11.2
A facile method for the preparation of β‐boryl‐α‐silyl aryl acrylamides using phenyllithium, dimethylphenylsilylpinacolborane, and propargylamides is reported. A key feature of this transition metal‐free reaction is the Brønsted base deprotonation of aryl secondary propargylamide to produce a Lewis base that activates the B−Si bond, which is followed by a sequential intramolecular α‐silylation‐trans‐β‐borylation