METHANESULFONYL BROMIDE, BROMO

B romo-3,4-di methoxybenzaldehyde eye1ohexy1i mi ne Cyelohexanami ne, N-[(2-brofflo-4,b-dimethoxyphenyl)methylene]- (73252-55-8), 65, 108 BROMOMETHANESULFONYL BROMIDE METHANESULFONYL BROMIDE, BROMO- ... 

This procedure illustrates a recently published, simple, general method for the synthesis of conjugated dienes from olefins. The scope of the reaction is shown in Table I.5 In most of these examples hydrogen bromide. .elimination can be effected by stirring a solution of the olefin-bromo-methanesulfonyl bromide adduct in methylene chloride with one equivalent of triethylamine at room temperature. Only two equivalents of the more costly potassium tert-butoxide are then needed in the second elimination step the yields using the two-base procedure are generally superior to that obtained using only potassium tert-butoxide. 

Dienes Allyldiphenylphosphine. Bromo-methanesulfonyl bromide. 1,3,3a,4,7,7a-Hexahydro-4,7-methanobenzo [c] thiophene 2,2-dioxide. Molybdenum carbonyl. Nickel(II) chloride-Zinc. 3-Sulfolene. Te-trakis(triphenylphosphine)palladium. 

Alkylation of (585b) with a phenacyl bromide produced (589), which can be cyclized with hydrazine to (590) (77JHC59). Similar cyclizations have been carried out on a 1-phenacyl-2-brpmoimidazole derivative (74UKZ99), a l-phenacyl-2-methanesulfonyl-imidazole derivative (74CHE1492) and l-(2-chloroethyl)-2-bromo-4,5-diphenylimidazole (75CHE371) to afiford imidazo[2,l-c][l,2,4]triazines. 

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