Stereoselective Biginelli-like reaction catalyzed by a chiral phosphoric acid bearing two hydroxy groups

• Xiaoyun Hu,
• Jianxin Guo,
• Cui Wang,
• Rui Zhang and
• Victor Borovkov

Beilstein J. Org. Chem. 2020, 16, 1875–1880, doi:10.3762/bjoc.16.155

• regioselective transformation of chiral 1,1,4,4-tetraphenylbutanetetraol obtained from natural tartaric acid. The chiral phosphoric acid was successfully applied as asymmetric catalyst in the Biginelli-like reaction affording the products in good yields and enantioselectivities of up to 95%. A control experiment

• catalyst effectively catalyzed Biginelli-like reactions with moderate to good enantioselectivities. Control experiments indicated that the presence of the two hydroxy groups were indispensable for achieving a high enantioselectivity. Keywords: asymmetric Biginelli-like reaction; chiral 1,1,4,4

• -tetraphenylbutanetetraol; chiral phosphoric acid; Introduction Dihydropyrimidinethiones (DHPMs) are an important class of heterocyclic compounds featuring in a large number of natural and artificial compounds possessing various biological activities, and serving as key intermediates for the synthesis of medical drugs [1