1451929-33-1Relevant articles and documents
Iridium-Catalyzed Enantioselective C(sp3)–H Borylation of Cyclobutanes
Chen, Xiang,Chen, Lili,Zhao, Hongliang,Gao, Qian,Shen, Zhenlu,Xu, Senmiao
, p. 1533 - 1537 (2020)
We herein report the first example of iridium-catalyzed enantioselective C(sp3)–H borylation of cyclobutanes using benzoxazoline as the directing group. The combination of a chiral bidentate boryl ligand and an iridium precursor has found to effectively catalyze C(sp3)–H borylation to afford a variety of cyclobutylboronates with good to excellent enantioselectivities. We also demonstrate the synthetic utility of the current method by converting the stereogenic C—B bond to other functionalities.
Copper-free asymmetric allylic alkylation with a grignard reagent: Design of the ligand and mechanistic studies
Grassi, David,Dolka, Chrysanthi,Jackowski, Olivier,Alexakis, Alexandre
supporting information, p. 1466 - 1475 (2013/02/25)
The Cu-free asymmetric allylic alkylation, catalysed by NHC, with Grignard reagents is reported on allyl bromide derivatives with good results. The enantioselectivity was quite homogeneous (around 85 % ee) on large and various substrates, regardless of the nature of the Grignard reagent. The formation of stereogenic quaternary centres was highly regioselective for both aliphatic and aromatic derivatives with good enantiomeric excess (up to 92 % ee). The methodology developed was found to be complementary with the Cu-catalysed version. Several new NHCs were tested with improved efficiency. In addition, mechanistic studies, using NMR spectroscopy, led to the discovery of the catalytically active species. Copyright