Grignard reagent, 3- propylmagnesium chloride

Quinoxaline readily reacts with Grignard reagents. Addition of two molecular proportions of allylmagnesium bromide and of 3-(dimethylamino)propylmagnesium chloride, and hydrolysis of the initial adducts, gives the tetrahydroquinoxalines 2 and 3, respectively. The 1 1 adducts 4, 5, and 6 are obtained from the reaction of quinoxaline with diphenylcyclopropenone, diphenylcyclopropenethione, and methyl phenylhydrazonochloroacetate in the presence of triethylamine, respectively. In the latter case the presumed intermediate is the dipolar... 

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