Department of Chemistry, National University of Singapore, 4 Science Drive 2, Singapore 117544, Republic of Singapore.
Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou 350207, China.
Org Lett. 2021 Apr 16;23(8):2884-2889. doi: 10.1021/acs.orglett.1c00505. Epub 2021 Mar 26.
We present herein a highly diastereo- and enantioselective Pd-catalyzed [4 + 2] cycloaddition of benzofuran-derived azadienes with vinyl benzoxazinanones, which represents a rare highly stereoselective cycloaddition of this class of fused azadienes as a two-atom synthon. The use of a phosphoramidite ligand bearing a chiral secondary amine with a simple biphenyl backbone proved to be the key to construct the novel spirocyclic tetrahydroquinoline scaffold containing three contiguous stereocenters as a single diastereomer in high enantioselectivity.
我们在此展示了一种高度非对映选择性和对映选择性的钯催化[4 + 2]环加成反应，该反应涉及苯并呋喃衍生的氮杂二烯与乙烯基苯并恶嗪酮的反应，这代表了这类稠合氮杂二烯作为双原子合成子的罕见的高度对映选择性环加成反应。使用带有简单联苯骨架的手性仲胺的磷酰胺配体被证明是构建新型螺环四氢喹啉骨架的关键，该骨架作为单一非对映异构体以高对映选择性包含三个连续的立体中心。
