Synthesis, X-Ray Structure Analysis and Topochemical Photopolymerization of 2,5-Dimethoxyphenyl- and Quinone-substituted Octa-3,5-diynes
摘要:
The octa-3,5-diynes 3a-g have been synthesized. Subsequent oxidation of 3a-g gave the 1,8-quinone-substituted octa-3,5-diynes 4a-g. The molecular structures of the diynes alpha-3b, beta-3b, 3c, 3e, 3f and 4f have been determined by X-ray diffraction. UV-irradiation of diyne 3e afforded in a single crystal-to-single crystal transformation the highly-ordered polymer 5 under topochemical control. The transformation of 3c into polymer 5 was observed by X-ray diffraction analysis. Irradiation of 4d yielded the first quinone-substituted intensive-blue poly(but-1-en-3-ynylene) 5, which turned red after work up. (C) 2000 Elsevier Science Ltd. All rights reserved.
Superoxide mediated isomerization of 4-aryl-but-1-ynes to 1-aryl-1,3-butadienes
摘要:
A new role of superoxide ion in the isomerization of homobenzylic acetylenes leading to 1-aryl-1,3-butadienes is reported. The unconventional reagent 1(02 is found to be superior in performing this kind of isomerization over other the commonly used bases. For substrates containing arene moiety and triple bond connected through more than two methylene groups, and for propargylcyclohexanol the reagent selectively effected migration of the triple bond. Reactivity of 1(02 towards the substrates having disubstitution at benzylic position varied depending on the nature of the substitution, alkyl-substitution lead to isomerization to give mixture of allene (an intermediate in the isomerization of acetylene to 1,3-butadiene) and triple bond migration product; whereas phenyl-substituted compound gave 1,3-diene. The utility of the methodology was demonstrated through a Diels-Alder reaction of one of the dienes obtained by the isomerization with suitable dienophiles. (C) 2015 Elsevier Ltd. All rights reserved.
Superoxide mediated isomerization of 4-aryl-but-1-ynes to 1-aryl-1,3-butadienes
作者:Faiz Ahmed Khan、Basavaraj M. Budanur
DOI:10.1016/j.tet.2015.07.075
日期:2015.10
A new role of superoxide ion in the isomerization of homobenzylic acetylenes leading to 1-aryl-1,3-butadienes is reported. The unconventional reagent 1(02 is found to be superior in performing this kind of isomerization over other the commonly used bases. For substrates containing arene moiety and triple bond connected through more than two methylene groups, and for propargylcyclohexanol the reagent selectively effected migration of the triple bond. Reactivity of 1(02 towards the substrates having disubstitution at benzylic position varied depending on the nature of the substitution, alkyl-substitution lead to isomerization to give mixture of allene (an intermediate in the isomerization of acetylene to 1,3-butadiene) and triple bond migration product; whereas phenyl-substituted compound gave 1,3-diene. The utility of the methodology was demonstrated through a Diels-Alder reaction of one of the dienes obtained by the isomerization with suitable dienophiles. (C) 2015 Elsevier Ltd. All rights reserved.
Synthesis, X-Ray Structure Analysis and Topochemical Photopolymerization of 2,5-Dimethoxyphenyl- and Quinone-substituted Octa-3,5-diynes
作者:Hermann Irngartinger、Markus Skipinski
DOI:10.1016/s0040-4020(00)00500-7
日期:2000.9
The octa-3,5-diynes 3a-g have been synthesized. Subsequent oxidation of 3a-g gave the 1,8-quinone-substituted octa-3,5-diynes 4a-g. The molecular structures of the diynes alpha-3b, beta-3b, 3c, 3e, 3f and 4f have been determined by X-ray diffraction. UV-irradiation of diyne 3e afforded in a single crystal-to-single crystal transformation the highly-ordered polymer 5 under topochemical control. The transformation of 3c into polymer 5 was observed by X-ray diffraction analysis. Irradiation of 4d yielded the first quinone-substituted intensive-blue poly(but-1-en-3-ynylene) 5, which turned red after work up. (C) 2000 Elsevier Science Ltd. All rights reserved.