School of Chemistry and Chemical Engineering, South China University of Technology , Guangzhou 510640, China.
Org Lett. 2016 Mar 18;18(6):1470-3. doi: 10.1021/acs.orglett.6b00416. Epub 2016 Mar 9.
Cyclopropanation of 2-aminoacrylates with N-tosylhydrazones could proceed smoothly under transition-metal-free conditions via a [3 + 2] cycloaddition process. This robust protocol exhibits excellent generality, delivering a wide spectrum of cyclopropane α-amino acid esters bearing contiguous quaternary carbon centers in high yields and diastereoselectivities. With these readily available products, the steric convergence of cyclopropane α-amino acids could be readily obtained.
2-氨基丙烯酸酯与 N-对甲苯磺酰腙的环丙烷化反应可以在无过渡金属条件下通过[3 + 2]环加成过程顺利进行。该反应具有很好的通用性，以高产率和高非对映选择性得到了一系列具有连续季碳原子的环丙烷α-氨基酸酯。利用这些易得的产物，可以很容易地获得环丙烷α-氨基酸的立体收敛。
