论文部分内容阅读
1 Results Tailored monomers based on the activated esters of 2,5-dibromobenzoic (sulfonic) acid derivatives, the 3-substituted 2,5-dibromothiophenes, the 9-substituted 2,7-dibromocarbazoles, and on the brominated 1,10-phenanthrolines suitable for Suzuki, Yamamoto or Grignard metathesis (GRIM) coupling reactions were synthesized and characterized by melting point, elemental analysis, 1H NMR, FTIR and TLC. The Horner-Wadsworth-Emmons reaction mechanism was utilized for the preparation of the 3-[2-(pyren-1-yl)vinyl]- or 3-[2-(quinolin-1-yl)vinyl]-2,5-dibromothiophenes. 4-Nitrophenol or N-hydroxysuccinimide were used for the preparation of activated esters. The Cadogan ring closure was utilized for the synthesis of 2,7-dibromocarbazole derivatives. A monomer with β-diketone structure was prepared and characterized as well. 1,10-Phenanthroline (phen) is a typical β-deficient aromatic compound and experience (and literature) advises that simple bromination is poor and nonselective. Of course, bromo derivatives can be obtained by the Skraup synthesis, but the low-yield and multi-step procedure is tedious. There are two main reasonable procedures available at present for the synthesis of 3,8-dibromo-1,10-phenanthroline. The methods utilize either phen monohydrochloride monohydrate for bromination or phen with addition of pyridine and sulfur chloride S2Cl2. We have found in our laboratory that the replacement of sulfur chloride by sulfur dichloride SCl2 and the use of phen monohydrate gives the possibility to prepare 3-bromo-, 3,8-dibromo-, 3,5,8-tribromo- and 3,5,6,8-tetrabromo-1,10-phenanthrolines in reasonable yields, and these derivatives can be separated by crystallization or by column chromatography.
1 Results Tailored monomers based on the activated esters of 2,5-dibromobenzoic (sulfonic) acid derivatives, the 3-substituted 2,5-dibromothiophenes, the 9-substituted 2,7-dibromocarbazoles, and on the brominated 1,10-phenanthrolines Suitable for Suzuki, Yamamoto or Grignard metathesis (GRIM) coupling reactions were synthesized and characterized by melting point, elemental analysis, 1H NMR, FTIR and TLC. The Horner-Wadsworth-Emmons reaction mechanism was utilized for the preparation of the 3- [2 - (pyren-1-yl) vinyl] - or 3- [2- (quinolin-1-yl) vinyl] -2,5-dibromothiophenes. 4-Nitrophenol or N-hydroxysuccinimide were used for the preparation of activated esters. Cadmium ring closure was utilized for the synthesis of 2,7-dibromocarbazole derivatives. A monomer with β-diketone structure was prepared and characterized as well. 1,10-Phenanthroline (phen) is a typical β-deficient aromatic compound and experience literature) advises that simple bromination is poor and nonselective. Of cou rse, bromo derivatives can be obtained by the Skraup synthesis, but the low-yield and multi-step procedure is tedious. There are two main reasonable procedures available at present for the synthesis of 3,8-dibromo-1,10-phenanthroline. The methods of either phen monohydrochloride monohydrate for bromination or phen with addition of pyridine and sulfur chloride S2Cl2. We have found in our laboratory that the replacement of sulfur chloride by sulfur dichloride SCl2 and the use of phen monohydrate gives the possibility to prepare 3-bromo -, 3,8-dibromo-, 3,5,8-tribromo- and 3,5,6,8-tetrabromo-1,10-phenanthrolines in reasonable yields, and these derivatives can be separated by crystallization or by column chromatography.