- 作者: 廖俊臣; 林和盛
- 作者服務機構: Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 300, R.O.C.
- 中文摘要:
Cycloadditions of 3,5-di-t-butyl-o-benzoquinone with diphenylacetylene, dimethy acetylenedicarboxylaet, 3-hexyne, phenylacetylene, methyl propiolate, 1-octyne and 3-hydroxy-3-methyl-1-butyne were studied. The reactions occur periselectively across the diene moiety of 3,5-di-t-butyl-o-benzoquinone to give bicyclo[2.2.2]octa-5,7-diene-2,3-diones. In the cases of monosubstituted acetylenes, the reactions take place regioselectively. The selectivitiesare explained in terms of electronic and steric effects.
The cycloadditions of two masked 3,5-di-t-butyl-o-benzoquinones 7 and 8 with monosubstituted acetylenes, phenylacetylene, methyl propiolate, 1-octyne and 3-hydroxy-3-methyl-1-butyne were also examined. Compound 7 reacts with high regioselectivity to give only bicyclo[2.2.2]octa-5,7-diene-2,3-diones 10 upon subsequent hydrolysis; the high regioselectivity was explained as the result of coherent electronic and steric effects. Compound 8 reacts with monosubstituted acetylenes to give either 9 or 10 or both upon subsequent hydrolysis, depending on the nature of the substituents on acetylene. This results from the opposite influences of electronic and steric effects. - 英文摘要: --
- 中文關鍵字: Cycloaddition; 3,5-di-t-butyl-o-benzoquinone; masked 3,5-di-t-butyl-o-benzoquinones; substituted acetylenes; photolysis; bicyclo[2.2.2]oct-5,7-diene-2,3-diones.
- 英文關鍵字: Cycloaddition; 3,5-di-t-butyl-o-benzoquinone; masked 3,5-di-t-butyl-o-benzoquinones; substituted acetylenes; photolysis; bicyclo[2.2.2]oct-5,7-diene-2,3-diones.