Efficient one-pot synthesis of pyrido[2,3-d]pyrimidines catalyzed by nanocrystalline MgO in water

Abstract

The direct three-component condensation of 6aminouracil, 6-amino-2-thiouracil or 6-amino-1,3dimethyluracil, with arylaldehydes and malononitrile to generate a series of pyrido[2,3-d]pyrimidine derivatives has been carried out over nanocrystalline MgO with high efficiency in water as a green solvent at 80°C. The morphology and structure of the nanocrystalline MgO were characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The results confirmed the nanocrystalline MgO particle size is approximately 50 nm. This methodology offers significant improvements for the synthesis of pyrido[2,3-d]pyrimidine derivatives with regard to the yield of products, simplicity in operation, and green aspects by avoiding toxic catalysts and solvents.

Synthesis of substituted pyrrolo[2,3-d]pyrimidines and pyrido[2,3-d]pyrimidines in the one-pot condensation of 2-thio-6-aminouracil, arylglyoxals and CH-acids

“…Метою даної роботи є розробка загальних методів синтезу заміщенних піроло[2,3d]піримідинів 5a-g та піридо[2,3-d]піримідинів 6a-d,e в однореакторній конденсації 6-амінo-2-https://doi.org/10.26565/2220-637X-2019-32-05 тіоурацилу 1, гідратів арилгліоксалів 2a-g і N,N-диметилбарбітурової кислоти 3 або ациклічних β-дикарбонільних сполук 4а,b. Зазначимо, що в літературі описано синтез ароматичних похідних піридо [2,3-d]піримідинів за участю ароматичних альдегідів, 6-аміно-2-тіоурацилу та малонодинітрилу в присутності нанокаталізаторів [18,19] [23]. Повідомлялося і про синтез вказаних похідних в спиртовому середовищі з використанням 6-амінобарбітурових чи -тіобарбітурових кислот як 1,3-бінуклеофільних реагентів [24].…”

An Efficient Protocol for the Synthesis of Pyrido[2,3‐d]pyrimidines in Glycerol–Water Medium: Assessment by Green Chemistry Metrics

“…[18] Consequently, a number of synthetic approaches have been reported for the preparation of pyrido [2,3d]pyrimidine derivatives. [19][20][21][22] Moreover, the literature survey reveals that pyrido [2,3-d]pyrimidines are usually synthesized by condensation of aromatic aldehyde, malononitrile, and 6-aminouracil or its derivatives at different reaction conditions such as 1) tetra-n-butyl ammonium bromide (TBAB)/ ultrasonic irradiation/water/70°C/50 min; [23] 2) triethylbenzylammonium chloride (TEBAC)/water/90°C/6-10 h; [24] 3) nanocrystalline MgO/water/80°C/12-35 min; [25] 4) KF-Al 2 O 3 /ethanol/90°C/5-8 h; [26] 5) diammonium hydrogen phosphate (DAHP)/water-ethanol/reflux/2 h; [27] 6) DMF/reflux/ 20-30 h; [28] 7) NaBr/ethanol or acetonitreile/electrolysis/25-30 min; [29] 8) SBA-Pr-SO 3 H/solvent free/5-45 min; [30] 9) Al-HMS-20/ethanol/RT/12 h [31] ; and 10) thiamine hydrochloride/water/90°C/2-2.5 h. [32] By considering the pharmacological significance of pyrido [2,3d]pyrimidines and within the framework of green chemistry approach for the expansion of our previous success, [33] we herein report a clean, efficient, and ecofriendly protocol for the glycerolassisted catalyst-free synthesis of pyrido[2,3-d]pyrimidine derivatives by one-pot three-component condensation of aromatic aldehyde, malononitrile, and 6-aminouracil or 6-amino-1,3dimethyluracil (Scheme 1).…”

Introduction of a New Magnetic Nanocatalyst as an Organic‐inorganic Hybrid Framework for the Synthesis of Pyrano[2,3‐d]pyrimidinone(thione)s and Pyrido[2,3‐d]pyrimidines

“…Among the other important nitrogen‐containing compounds, pyrido[2,3‐ d ]pyrimidine derivatives have been under attention and investigation because of their various and wide biological properties such as antibacterial, antihypertensive and antifolate activities. Because of the high importance of these types of compounds, many catalysts and methods have been introduced for their preparation such as urea, MgO triethanolamine (TEOA), and SBA‐15‐Pr‐SO 3 H and γ ‐Fe 2 O 3 @Cu 3 Al‐LDH‐ N ‐amidinoglycine …”