A Convergent, Stereoselective Route to Trisubstituted Alkenyl Boronates
作者:Jean Michalland、Samir Z. Zard
DOI:10.1021/acs.orglett.1c03022
日期:2021.10.15
A modular, stereoselectiveroute to trisubstituted (Z)-alkenyl (MIDA)boronates is described, consisting of the radical addition–fragmentation of dithiocarbonates to 2-(MIDA)boronyl-3-(2′-fluoro-pyridyl-6′-oxy)-alkenes. The bulky (MIDA)boronate ensures a highly stereoselective fragmentation that is enhanced by the poor stabilization of the radical adjacent to the tetravalent boron atom. The vinyl boronate
Radical Fragment Coupling Route to Geminal Bis(boronates)
作者:Qi Huang、Samir Z. Zard
DOI:10.1021/acs.orglett.8b02235
日期:2018.9.7
atom abstraction and delivers a vast array of highly functional geminal bis(boronates). The ability to assemble geminal bis(boronates) bearing polar functional groups not readily obtained through existing methods is particularly noteworthy. This approach also opens up access to geminal bis(boronyl) cyclopropanes and geminal bis(boronyl) tetrahydroquinolines.
A Modular Access to 1,2‐ and 1,3‐Disubstituted Cyclobutylboronic Esters by Consecutive Radical Additions
作者:Jean Michalland、Nicolas Casaretto、Samir Z. Zard
DOI:10.1002/anie.202113333
日期:2022.1.17
Using the strain inherent in a cyclobutyl ring to counteract the stabilization of a radical adjacent to a boronic ester allows the synthesis a broad variety of 1,2- and 1,3-disubstituted cyclobutylboronic esters.
Adducts from the radical addition of xanthates to ethyl vinyl sulfide readily undergo elimination of the xanthate group upon thermolysis to give vinylic and/or allylic sulfides, depending on the structure. In the case of α-xanthyl ketones, the adducts are converted into α-keto vinyl carbinols by rearrangement of the sulfoxides derived from the vinylic and allylic sulfides.
作者:Béatrice Quiclet-Sire、Guillaume Revol、Samir Z. Zard
DOI:10.1016/j.tet.2010.05.107
日期:2010.8
Various xanthates can be added to N-vinyl phthalimide with little formation of oligomers, if the xanthate is used in excess and the medium slightly diluted. The adduct xanthates thus obtained can in turn undergo radical additions to numerous olefins, providing a convergent and modular access to densely functionalized amines. (C) 2010 Elsevier Ltd. All rights reserved.