Biginelli-like three component reaction: Synthesis of some new ethyl 6-ethoxycarbonylmethyl-4-aryl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate derivatives

FeNH4(SO4)2·12H2O (alum)-catalyzed preparation of 1,4-dihydropyridines: improved conditions for the Hantzsch reaction

Abstract

FeNH₄(SO₄)₂·12H₂O (alum) efficiently catalyzes the one-pot three-component reaction of dimedone, aldehydes, and 3-aminocrotonate to afford 1,4-dihydropyridines. The work-up is easy, and the products are obtained in good to excellent yields and high purity.

Graphical abstract

Ethyl 6-ethoxy-carbonyl-methyl-4-(2-hydroxy-phen-yl)-2-oxo-1,2,3,4-tetra-hydro-pyrimidine-5-carboxyl-ate

The title compound, C(17)H(20)N(2)O(6), belongs to the monastrol-type of anti-cancer agents and was selected for crystal structure determination in order to confirm its mol-ecular structure and explore some aspects of its structure-activity relationships. The central tetra-hydro-pyrimidine ring has a flat-envelope conformation. The 4-hydroxy-phenyl group occupies a pseudo-axial position and is inclined at an angle of 87.7 (2)° to the mean plane of the heterocyclic ring. Of the two ethyl ester groups, one (in the 5-position) is in a coplanar and the other (in the 6-position) is in a perpendicular orientation with respect to the heterocyclic plane. There is a three-dimensional hydrogen-bonding network in which all hydrogen-bond donors and acceptors are involved.