[摘要]:An efficient and organocatalyzed asymmetric reaction of phenacyl halides with coumarin-based dihydrobenzothiazoles was developed to afford cis-2,3-disubstituted 3,4-dihydro-2H-benzothiazines. This method provides a one-step and highly diastereoselective route to a wide variety of coumarin-based 3,4-dihydro-2H-benzothiazines using the cheap and commercially available Cinchona alkaloid quinine hydrochloride.