Synthesis of 3,5-disubstituted pyridazines by regioselective [4+2] cycloadditions with ethynyltributyltin and subsequent replacement of the organotin substituent

Article abstract of DOI:10.1016/S0040-4020(98)00127-6

Cycloadditions of 3-aryl-1,2,4,5-tetrazines 1a-o with ethynyltributyltin S occur with high regioselectivity to yield 3-aryl-5-tributylstannyl- pyridazines 9-23 in 71-95% yield. Moreover, the stannanes obtained could be utilized as starting materials for t