1,3,5-triaryl-2-pyrazolines is described. The solvent ethyl lactate, obtained from renewable sources, is biodegradable. The catalyst \(\hbox CeCl}_3} \cdot 7\hbox H}_2}\hbox O}\) is a water-tolerant Lewis acid with low toxicity. Easy and clean work up, recyclable solvent and catalyst are merits of the protocol. The reaction works well for all systems giving good yields of the desired products.
Nanorod vanadatesulfuric acid (VSA NRs), as a recyclable and ecologically benign catalyst, was used for the one‐pot synthesis of chalcones and 1,3,5‐triaryl‐2‐pyrazolines (TAPs). Chalcones were prepared via the condensation of substituted acetophenones with aryl‐aldehydes under solvent‐free conditions. Subsequently, the synthesized chalcones were used for the catalytic synthesis of TAPs via two‐component
The visible light mediated oxidation of 1,3,5-trisubstitutedpyrazolines under metal-free conditions was developed. Various substituted pyrazolines were oxidized to pyrazoles by irradiation with visible light/sunlight. A plausible mechanism was proposed for the light mediated oxidation proceeding via formation of intermediates with electron rich C-3 positions and electron deficient C-5 positions. Correlation
possible intermediate carbocations. The synthetic utility of a green solvent has been explored by synthesizing some of pyrazolines in a DES medium. The synthetic application of the present methodology is employed in the synthesis of a pyrazoline alkaloid.
TfOH 介导容易获得从醛、苯肼和苯乙烯开始的有趣的吡唑啉。通过以非常高的收率和非常高的区域选择性合成各种 1,3,5-三取代的吡唑啉,探索了这种合成方法的范围。通过比较可能的中间碳阳离子的稳定性来解释区域选择性的起源。通过在 DES 介质中合成一些吡唑啉,探索了绿色溶剂的合成效用。本方法的合成应用用于吡唑啉生物碱的合成。