A novel nucleophilic substitution of pyridazines is found, in which phenoxy group is dislodged rather than the halogen atom, on treating 3-halo-6-phenoxypyridazines with alkoxy anion. The reactivity of substituents on...A novel nucleophilic substitution of pyridazines is found, in which phenoxy group is dislodged rather than the halogen atom, on treating 3-halo-6-phenoxypyridazines with alkoxy anion. The reactivity of substituents on benzene ring and the halogen atom of pyridazines are studied. Reasonable explanation based on the quantum chemical calculations are given.展开更多
The hydrohalogenation reaction of 1-alkyl substituted 1,2-allenyl carboxylic acid esters (1) with MX (M= Na, or Li, X= Cl, Br, I) afforded a mixture of β,γ-unsaturated 3-halo–3-alkenoates (2) and Q,P unsaturated 3-...The hydrohalogenation reaction of 1-alkyl substituted 1,2-allenyl carboxylic acid esters (1) with MX (M= Na, or Li, X= Cl, Br, I) afforded a mixture of β,γ-unsaturated 3-halo–3-alkenoates (2) and Q,P unsaturated 3-halo-2-alkenoates (3) in HOAc, while using a mixture of HOAC-CF3CO2H (1:1) or CF3C2H as the reaction medium the corresponding reaction cleanly produced β,γ -unsaturated 3-hale3-alkenoates (2) as the sole products in high yields. The subsequent coupling reactions were studied.展开更多
文摘A novel nucleophilic substitution of pyridazines is found, in which phenoxy group is dislodged rather than the halogen atom, on treating 3-halo-6-phenoxypyridazines with alkoxy anion. The reactivity of substituents on benzene ring and the halogen atom of pyridazines are studied. Reasonable explanation based on the quantum chemical calculations are given.
基金National Natural Science Foundation of China (No. 29525202)Shanghai Municipal Cormnittee of Science and Technology (No. 98QA14001).
文摘The hydrohalogenation reaction of 1-alkyl substituted 1,2-allenyl carboxylic acid esters (1) with MX (M= Na, or Li, X= Cl, Br, I) afforded a mixture of β,γ-unsaturated 3-halo–3-alkenoates (2) and Q,P unsaturated 3-halo-2-alkenoates (3) in HOAc, while using a mixture of HOAC-CF3CO2H (1:1) or CF3C2H as the reaction medium the corresponding reaction cleanly produced β,γ -unsaturated 3-hale3-alkenoates (2) as the sole products in high yields. The subsequent coupling reactions were studied.
