37385-35-6Relevant academic research and scientific papers
Copper-catalyzed aerobic 6-endo-trig cyclization of β,γ-Unsaturated Hydrazones for the Divergent Synthesis of Dihydropyridazines and Pyridazines
Fan, Zhenwei,Pan, Zhangjin,Huang, Liangsen,Cheng, Jiajia
, p. 4236 - 4245 (2019)
A divergent synthetic strategy to 1,6-dihydropyridazines and pyridazines through Cu(II)-catalyzed controllable aerobic 6-endo-trig cyclization was developed. The selectivity can be rationally tuned via the judicious choice of reaction solvent. It was found that the 1,6-dihydropyridazines were obtained in moderate to high yields with CH3CN as the reaction solvent, whereas employment of AcOH directly afforded pyridazines in up to 92% yields, probably arising from the oxidation of the in situ generated 1,6-dihydropyridazines.
Synthesis of 1,4,5,6-tetrahydropyridazines and pyridazines: Via transition-metal-free (4 + 2) cycloaddition of alkoxyallenes with 1,2-diaza-1,3-dienes
Wu, Qi,Shao, Pan-Lin,He, Yun
, p. 21507 - 21512 (2019/07/22)
We developed an economical and practical protocol for the synthesis of 1,4,5,6-tetrahydropyridazines. A diverse range of alkoxyallenes and 1,2-diaza-1,3-dienes undergo (4 + 2) cycloaddition to generate the desired products in excellent yields. The high efficiency, wide substrate scope and good functional group tolerance of this process, coupled with operational simplicity, render the method synthetically attractive. The utility of the cycloaddition is also demonstrated by the preparation of various pyridazines from 1,4,5,6-tetrahydropyridazines.
