The regioselective conjugate addition of alkenylboronic acids to electronically-differentiated
1,4-enedicarbonyl compounds under metal-free conditions, using tartaric acid as promoter
of the reaction is reported. The resulting compounds have been used as starting materials
in the synthesis of 4-alkenyl-4,5-dihydropyridazin-3(2H)-ones or 4-alkylpyridazin-3(2H)-ones by reaction with hydrazine hydrate and acetic acid.
Key words
boron - cyclization - isomerization - Michael addition - nucleophilic addition
