Catalyzed by Ir[dF(CF3)ppy]2(dtbbpy)PF6, the coupling of potassium organotrifluoroborates with Baylis–Hillman derivatives under visible light irradiation has been developed. Based on the mechanism of reductive quenching cycle, it provides an easy, mild, efficient method for the synthesis of a variety of α,β-unsaturated carboxylic estersderivatives in a broad scope of the substrates.
A biologically inspired organocatalytic one‐pot synthesis of highly functionalized pyridazines, which are ubiquitous structural units in a number of biologically active compounds, has been developed by starting from readily available diazo compounds and Morita–Baylis–Hillman (MBH) carbonates. Under mild reaction conditions, this synthetic route tolerated significant substrate variation to deliver a
A Highly Regio- and Diastereoselective Phosphane-Catalyzed [3+2] Annulation of Morita-Baylis-Hillman Carbonates with Cyclic<i>N</i>-Acyl Ketimines
作者:Li-Jun Yang、Hua Cai、Jing Nie、Jun-An Ma
DOI:10.1002/ejoc.201300342
日期:2013.7
A highlyregio- and diastereoselectivephosphane-catalyzed [3+2] annulation of Morita–Baylis–Hillman (MBH) carbonates with cyclic N-acyl-substituted ketimines was developed. In the presence of the catalyst PBu3 (10 mol-%), a series of N-fused tricyclic products were obtained in excellent yields and diastereoselectivities under mild conditions. An example of a catalytic enantioselective annulation is
An efficient method for the regioselective synthesis of potentially biologically active tetrasubstituted 1-pyrazolines has been achieved via a 1,3-dipolar cycloaddition reaction. A range of tetrasubstituted 1-pyrazolines bearing one Boc group and two ester groups were obtained in high yields (up to 99%). The structure and relative stereochemistry of cycloadducts were confirmed by NMR spectra and single