Chandan Gharui, Satya Prakash, Deepak Chopra and Subhas Chandra Pan
Org. Biomol. Chem., 2020,18, 2828-2833
DOI:
10.1039/D0OB00568A,
Communication
Herein we have developed the first enantioselective synthesis of 5-substituted-5H-benzoxathiepine-2(3H)-ones. 2-Sulfonylmethyl phenols and thioglycolates were employed as reaction partners in this method. The desired thia Michael products were obtained via bifunctional squaramide catalyzed conjugate addition reaction to in situ generated o-quinone methides and then basic hydrolysis followed by cyclization led to the formation of 5-substituted-5H-benzoxathiepine-2(3H)-ones. Broad scope and moderate to high enantioselectivities were observed for both products.