134142-28-2Relevant academic research and scientific papers
1,3-Dipolar Cycloaddition of 2-Diazoalkanes to Pyridazin-3(2H)-one Derivatives. The Formation of 3H-Pyrazolopyridazin-4(5H)-one and 3H-Pyrazolopyridazin-7(6H)-one Derivatives
Stimac, Anton,Stanovnik, Branko,Tisler, Miha
, p. 417 - 423 (2007/10/02)
1,3-Dipolar cycloadditions of diazoalkanes to pyridazin-3(2H)-ones 1-7 and pyridazin-3(2H)-thiones 8 and 9 are regioselective producing 3H-pyrazolopyridazin-4(5H)-ones 15-19, 27-29 and 34-38 as the major products.In some instances, the isomeric 3H-pyrazolopyridazin-7(6H)-ones, such as 20 and 23 were isolated as the minor products.From 3 and 6 the primary 3a,7a-dihydro cycloadducts 25 and 26, and rearranged 1,2-dihydro intermediate 31 were isolated.From 10 and 1-diazoindane the isomeric exo- and endo-spiro products 39 and 40 were formed.
