Modular, Catalytic Enantioselective Construction of Quaternary Carbon Stereocenters by Sequential Cross-Coupling Reactions
作者:Bowman Potter、Emma K. Edelstein、James P. Morken
DOI:10.1021/acs.orglett.6b01580
日期:2016.7.1
chiral γ,γ-disubstituted allylboronates in the presence of RuPhos ligand occurs with high regioselectivity and enantiospecificity, furnishing nonracemic compounds with quaternary centers. Mechanistic experiments suggest that the reaction occurs by transmetalation with allyl migration, followed by rapid reductive elimination.
Synthesis of Vinyl Boronates from Aldehydes by a Practical Boron–Wittig Reaction
作者:John R. Coombs、Liang Zhang、James P. Morken
DOI:10.1021/acs.orglett.5b00480
日期:2015.4.3
A highly stereoselectiveboron-Wittigreaction between stable and readily accessible 1,1-bis(pinacolboronates) and aldehydes furnishes a variety of synthetically useful di- and trisubstituted vinyl boronate esters.
Dual Functionalization of α‐Monoboryl Carbanions through Deoxygenative Enolization with Carboxylic Acids
作者:Wei Sun、Lu Wang、Chungu Xia、Chao Liu
DOI:10.1002/anie.201801679
日期:2018.5.4
1‐diborylalkanes through deoxygenative enolization with carboxylicacids was developed. 1,1‐Diborylalkanes were activated by MeLi to generate α‐monoboryl carbanions. In situ IR spectroscopy indicated an interaction between carboxylicacid and 1,1‐diborylalkane before addition of the activation reagent. Release of the active α‐monoboryl carbanion from the masked form was necessary for its reaction with carboxylate
C–O Functionalization of α-Oxyboronates: A Deoxygenative <i>gem</i>-Diborylation and <i>gem</i>-Silylborylation of Aldehydes and Ketones
作者:Lu Wang、Tao Zhang、Wei Sun、Zeyu He、Chungu Xia、Yu Lan、Chao Liu
DOI:10.1021/jacs.7b02518
日期:2017.4.12
the success of this transformation is the base-promoted C-O bond borylation or silylation of the generated α-oxyboronates. Experimental and theoretical studies exhibit that the C-O bond functionalization proceeds via an intramolecular five-membered transition-state (9-ts) boryl migration followed by a 1,2-metalate rearrangement with OBpin as a leavinggroup. The transformation occurs with an inversion