Electrocatalytic and chemical assembling of N,N′-dialkylbarbituric acids and aldehydes: efficient cascade approach to the spiro-[furo[2,3-d]pyrimidine-6, 5′-pyrimidine]-2,2′,4,4′,6′-(1′H,3H,3′H)-pentone framework

Electrocatalytic assembling of aldehydes and N,N'-dialkylbarbituric acids leads to selective and efficient formation of substituted 1,5-dihydro-2H,2'H-spiro[furo[2,3-d]pyrimidine-6,5'-pyrimidine]-2,2',4,4',6'-(1'H,3H,3'H)-pentones in 70-85% yields as a result of the complex cascade process. The electrocatalytic process smoothly proceeds with aromatic aldehydes bearing both electron-donating and electron-withdrawing groups, and allows for the selective and efficient one-step formation of spirobarbiturates containing furo[2,3-d]pyrimidine scaffold, which are a perspective class of compounds with prominent pharmacological and physiological activity. The application of the effective electrocatalytic cascade method to the formation of medicinally relevant spiro[furo[2,3-d]pyrimidine-6,5'-pyrimidine]-2,2',4,4',6'-(1'H,3H,3'H)-pentones is also beneficial from the viewpoint of diversity-oriented large-scale processes and represents a novel, facile and environmentally benign synthetic concept for electrocatalytic cascade reaction strategy. (C) 2011 Elsevier Ltd. All rights reserved.