Introduction of a new synthetic route about 33050-38-3

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 3,6-Dichloro-[1,2,4]triazolo[4,3-b]pyridazine, and friends who are interested can also refer to it.

Synthetic Route of 33050-38-3, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 33050-38-3 name is 3,6-Dichloro-[1,2,4]triazolo[4,3-b]pyridazine, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

General procedure: Appropriate 6-chloro-[1 ,2,4]triazolo[4,3-b]pyridazine (1 eq) or 6-chloro- [1 ,2,4]triazolo[3,4-a]phtalazine (1 eq), potassium carbonate (3 to 4 eq) and the appropriate phenol, thiophenol (1 to 4 eq, 1 eq is preferentially used when R1 = CI) were dissolved in ?,?-dimethylformamide under nitrogen atmosphere. The reaction mixture was stirred overnight at room temperature or at 100-1 10C, or 5-30 minutes at 100-170C on microwave irradiation. The reaction mixture was diluted with ethyl acetate and washed with brine. The organic layer was dried over Na2S04, filtered and evaporated to dryness. The residue was purified by chromatography on silica gel, precipitated, triturated in the appropriate solvent, or used without further purification to obtain the desired 6-aryl-[1 ,2,4]triazolo[4,3-b]pyridazine, or 6-aryl-[1 ,2,4]triazolo[3,4-a]phtalazine.This protocol was used to prepare the following compounds: Cpd.1 -1 , Cpd.1 -3, Cpd.1 -4, Cpd.1 -7, Cpd.1 -8, Cpd.1 -9, Cpd.1 -10, Cpd.1 -1 1 , Cpd.1 -12, Cpd.1 -13, Cpd.1 -14, Cpd.2-1 , Cpd.2-3, Cpd.2-4 and other compounds of the invention that contain a biphenyloxy, a pyridinylphenyloxy, a thiazolylphenyloxy, or a thiopenylphenyloxy group in the 6-substituted position of the [1 ,2,4]triazolo[4,3-b]pyridazines or 6-substituted position of the [1 ,2,4]triazolo[3,4-a]phthalazine (but further information about conditions and purification are reported in Tables of Example 2).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 3,6-Dichloro-[1,2,4]triazolo[4,3-b]pyridazine, and friends who are interested can also refer to it.

Reference:
Patent; GENFIT; BOUROTTE, Maryline; DELHOMEL, Jean-Francois; DUBERNET, Mathieu; GOUY, Marie-Helene; WO2013/45519; (2013); A1;,
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics