With 4 methyl 4′ nitrodibenzene ether,thiourea dioxide and sodium hydroxide as starting materials,the 4 methyl 4′ aminodibenzene ether is synthesized in aqueous ethanolic solution.The optimum conditions of the react...With 4 methyl 4′ nitrodibenzene ether,thiourea dioxide and sodium hydroxide as starting materials,the 4 methyl 4′ aminodibenzene ether is synthesized in aqueous ethanolic solution.The optimum conditions of the reaction are as follows∶4 melthyl 4′ nitrodibenzene ether∶thiourea dioxide∶sodium hydroxide is 1.0mol∶3.9mol∶7.5mol,the duration of additron of thiourea dioxide for the present scale is 1.0h,suitable temperature is 50℃,reaction time is 40min.The yield of 4 methyl 4′ aminodibenzene ether reaches 93.1%.展开更多
A modified [3+1] cyclization procedure for the synthesis of calix [4]arenes was developed by using diglycol dimethyl ether as the solvent in place of dioxane which was generally adopted in previous literature. By the ...A modified [3+1] cyclization procedure for the synthesis of calix [4]arenes was developed by using diglycol dimethyl ether as the solvent in place of dioxane which was generally adopted in previous literature. By the modified procedure, the yield of 5-bromo-11, 23-di-tert-butyl-17-methyl-25, 26, 27, 28-tetrahydroxycalix[4]arene from cyclic condensation of 2, 6-bis(2’-hydroxy-5’-tert-butyl-benzyl)-4-cresol and 2, 6-bis (bromomethyl)-4-bromophenol in the presence of TiCl4 was improved from less than 20％ to 40％, and the reaction time was reduced from several days to ten hours.展开更多
文摘With 4 methyl 4′ nitrodibenzene ether,thiourea dioxide and sodium hydroxide as starting materials,the 4 methyl 4′ aminodibenzene ether is synthesized in aqueous ethanolic solution.The optimum conditions of the reaction are as follows∶4 melthyl 4′ nitrodibenzene ether∶thiourea dioxide∶sodium hydroxide is 1.0mol∶3.9mol∶7.5mol,the duration of additron of thiourea dioxide for the present scale is 1.0h,suitable temperature is 50℃,reaction time is 40min.The yield of 4 methyl 4′ aminodibenzene ether reaches 93.1%.
文摘A modified [3+1] cyclization procedure for the synthesis of calix [4]arenes was developed by using diglycol dimethyl ether as the solvent in place of dioxane which was generally adopted in previous literature. By the modified procedure, the yield of 5-bromo-11, 23-di-tert-butyl-17-methyl-25, 26, 27, 28-tetrahydroxycalix[4]arene from cyclic condensation of 2, 6-bis(2’-hydroxy-5’-tert-butyl-benzyl)-4-cresol and 2, 6-bis (bromomethyl)-4-bromophenol in the presence of TiCl4 was improved from less than 20％ to 40％, and the reaction time was reduced from several days to ten hours.
