An efficient one-pot three-component synthesis of pyrimido[4,5-d]pyrimidine derivatives in aqueous medium

Novel and Green Preparation of Fe3O4@TiO2‐Immobilized‐ILs Based on DABCO for Highly Efficient Synthesis of Primido[4,5‐d]pyrimidines

“…Then, intermediate II is formed by nucleophilic attack of intermediate I to aromatic aldehyde in the presence of nanocatalyst. Finally, due to cyclization and dehydration of intermediate II, the desired product is obtained …”

“…Reusability of the Fe 3 O 4 @TiO 2 @ILs magnetic nanocatalyst dehydration of intermediate II, the desired product is obtained. [17,54]…”

TBHP-mediated oxidative synthesis of substituted pyrimido[4,5-d]pyrimidines fromN-uracil amidines and methylarenes under metal free conditions

“… 19 Tummaluru and co-workers also developed a one-pot protocol for the synthesis of 5,6-dihydropyrimido[4,5- d ]pyrimidines involving 6-amino- N , N -dimethyluracil, phenylisocyanate, and aromatic aldehydes in water solvent. 20 In another approach, Ghorbani-Vaghei and Sarmast employed a magnetic nanoparticle Fe 3 O 4 @SiO 2 as catalyst in water solvent for the synthesis of substituted pyrimido[4,5- d ]pyrimidines. 21 Nevertheless, these methods are associated with few shortcomings such as – harsh reaction conditions (high temperature, microwave), 16 a , b use of toxic solvents, use of metal catalysts, or use of complex synthetic pathways, 19 and less-environmentally benign, or not readily available substrates.…”

Green synthesis of new pyrimido[4,5‐d]pyrimidine derivatives using 7‐aminonaphthalene‐1,3‐disulfonic acid‐functionalized magnetic Fe3O4@SiO2 nanoparticles as catalyst

“…Few reported procedures are solvent‐free, while one of them uses water as solvent. However, these methods require forcing conditions, long reaction times, high energy and complex synthetic pathways . To overcome these difficulties, there is a need to develop more effective and sustainable chemical procedures for the synthesis of pyrimido[4,5‐d]pyrimidines.…”

“…Among them, the pyrido[2,3‐d]pyrimidines and pyrimido[4,5‐d]pyrimidines are an important class of annulated uracil with biological significance, such as antiallergic, anticancer, antihypertensive, vasodilators and bronchodilators agents . Moreover, various attempts that have been made towards the synthetic manipulation of uracil for the preparation of pyrimido[4,5‐d]pyrimidine derivatives include three‐component reactions, as well as cycloaddition reactions . Some of them use p ‐toluenesulfonic acid, AcOH and iodine as catalysts.…”