Premium
Concise Pyrimido[4,5‐ d ]pyrimidine Synthesis via Direct Annulation of N ‐Uracil Amidines with Benzaldehydes Under Transition Metal Free Conditions
Author(s) -
Debnath Pradip,
Sahu Gouranga,
De Utpal C.
Publication year - 2019
Publication title -
chemistryselect
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.437
H-Index - 34
ISSN - 2365-6549
DOI - 10.1002/slct.201900022
Subject(s) - annulation , chemistry , pyrimidine , uracil , transition metal , combinatorial chemistry , catalysis , base (topology) , organic chemistry , stereochemistry , mathematics , dna , mathematical analysis , biochemistry
A novel and concise route towards the synthesis of pyrimido[4,5‐ d ]pyrimidines via a direct annulation reaction of N ‐uracil amidines with benzaldehydes under transition metal free conditions has been described. The requisite precursors N ‐uracil amidines are obtained via S N AE reaction on 6‐chlorouracil with amidines. A series of pyrimido[4,5‐ d ]pyrimidines has been synthesized in good to excellent yields by the direct annulation of N ‐uracil amidines with benzaldehydes using Cs 2 CO 3 as base and molecular oxygen as oxidant in t BuOH at 100 0 C. This synthetic protocol has a number of advantages such as‐ operational simplicity, use of green oxidant, avoidance of transition metal catalysts or ligands, and easy accessibility of the starting materials, making it a highly practical approach to access various pyrimido[4,5‐ d ]pyrimidines of biological interest.