制备2,6-二甲基溴苯是一种溴代芳烃,可通过重氮化反应由2,6-二甲基苯胺为原料制得。
向含有65毫升48%盐酸溶液的初始进料中分批加入12.12克(0.1摩尔)2,6-二甲基苯胺。在80℃下搅拌所得浓悬浮液15分钟,随后冷却至-10℃,以不超过-5℃的速度于约1小时内滴加由35毫升水和8克(0.116摩尔)亚硝酸钠形成的溶液,并加入80毫克氨基磺酸。接着将冷却至-10℃的重氮盐悬浮液在约30分钟内计量送入已加热至80℃的含有13.9克(0.05摩尔)硫酸亚铁七水合物与65毫升62%盐酸溶液形成的混合物中。然后于80℃下继续搅拌反应混合物1小时,冷却至室温后与125毫升水混合,分离各相并以每次50毫升二氯甲烷萃取水相三次。再用25毫升水洗涤合并的有机相两次,干燥后减压浓缩,得到17.4克油状产物,经气相色谱分析显示该油状物含83%的2,6-二甲基溴苯(理论值为78%)。
化学性质淡黄色油状液体
类别有毒物品
毒性分级高毒
急性毒性静脉注射 - 小鼠 LD50: 56毫克/公斤
可燃性危险特性遇明火可燃;燃烧产生有毒溴化物
储运特性需存放在通风低温干燥的库房中,与氧化剂和食品添加剂分开存放
灭火剂中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
2,4-二甲基溴苯 | 1-bromo-2,4-dimethylbenzene | 583-70-0 | C8H9Br | 185.063 |
2-溴甲苯 | 2-methylphenyl bromide | 95-46-5 | C7H7Br | 171.037 |
2-溴-5-叔丁基-1,3-二甲基苯 | 4-t-butyl-2,6-dimethylbromobenzene | 5345-05-1 | C12H17Br | 241.171 |
中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
2,4-二甲基溴苯 | 1-bromo-2,4-dimethylbenzene | 583-70-0 | C8H9Br | 185.063 |
2,5-二溴间二甲苯 | 2,5-dibromo-1,3-dimethylbenzene | 100189-84-2 | C8H8Br2 | 263.96 |
2-溴-3-甲基苯甲醛 | 2-bromo-3-methylbenzaldehyde | 109179-31-9 | C8H7BrO | 199.047 |
3-甲基-2-溴苄溴 | 2-bromo-1-(bromomethyl)-3-methylbenzene | 66790-58-7 | C8H8Br2 | 263.96 |
[2-溴-3-(羟甲基)苯基]甲醇 | 2,6-dihydroxymethylbromobenzene | 59346-22-4 | C8H9BrO2 | 217.062 |
3,5-二甲基-4-溴苯腈 | 4-bromo-3,5-dimethylbenzonitrile | 75344-77-3 | C9H8BrN | 210.073 |
3,5-二甲基溴苯 | 5-bromo-1,3-xylene | 556-96-7 | C8H9Br | 185.063 |
2-溴苯-1,3-二甲醛 | 2-bromoisophthalaldehyde | 79839-49-9 | C8H5BrO2 | 213.03 |
2-溴-1,3-双(溴乙基)苯 | 2-bromo-1,3-bis(bromomethyl)benzene | 25006-88-6 | C8H7Br3 | 342.856 |
—— | 2-bromo-1,3-bis(mercaptomethyl)benzene | 123525-54-2 | C8H9BrS2 | 249.195 |
2-溴间苯二腈 | 2-bromoisophthalonitrile | 22433-90-5 | C8H3BrN2 | 207.029 |
4-溴-3,5-二甲基苯胺 | 4-bromo-3,5-dimethylaniline | 59557-90-3 | C8H10BrN | 200.078 |
—— | 1-bromo-2,6-bis(methoxymethyl)benzene | 65654-53-7 | C10H13BrO2 | 245.116 |
(2-溴-3-甲基苯基)乙腈 | 2-(2’-bromo-3’-methylphenyl)acetonitrile | 248920-09-4 | C9H8BrN | 210.073 |
—— | 2-Bromo-1-(2-chloroethyl)-3-methylbenzene | 512786-28-6 | C9H10BrCl | 233.535 |
2-(2-溴-3-甲基苯基)乙醇 | 2-(2-bromo-3-methylphenyl)ethanol | 248920-15-2 | C9H11BrO | 215.09 |
2,6-二(二氟甲基)溴苯 | 2,6-bis(difluoromethyl)bromobenzene | 79839-50-2 | C8H5BrF4 | 257.025 |
3-溴-2,4-二甲基-苯酚 | 3-bromo-2,4-dimethylphenol | 74571-81-6 | C8H9BrO | 201.063 |
2-溴-5-叔丁基-1,3-二甲基苯 | 4-t-butyl-2,6-dimethylbromobenzene | 5345-05-1 | C12H17Br | 241.171 |
1,3-双(二溴甲基)-2-溴苯 | 1,3-bis(dibromomethyl)-2-bromobenzene | 135590-51-1 | C8H5Br5 | 500.648 |
—— | 2-bromo-1,3-bis(cyanomethyl)benzene | —— | C10H7BrN2 | 235.083 |
3-溴-2,4-二甲基苯胺 | 3-bromo-dimethylaniline | 66314-77-0 | C8H10BrN | 200.078 |
Halodimethylsulfonium halide 1, which is readily formed in situ from hydrohaloic acid and DMSO, is a good nucleophilic halide. This activated nucleophilic halide rapidly converts aryldiazonium salt prepared in situ by the same hydrohaloic acid and nitrite ion to aryl chlorides, bromides, or iodides in good yield. The combined action of nitrite ion and hydrohaloic acid in DMSO is required for the direct transformation of aromatic amines, which results in the production of aryl halides within 1 h. Substituted compounds with electron-donating or -withdrawing groups or sterically hindered aromatic amines are also smoothly transformed to the corresponding aromatic halides. The only observed by-product is the deaminated arene (usually <7%). The isolated aryldiazonium salts can also be converted to the corresponding aryl halides using 1. The present method offers a facile, one-step procedure for transforming aminoarenes to haloarenes and lacks the environmental pollutants that usually accompany the Sandmeyer reaction using copper halides. Key words: aminoarenes, haloarenes, halodimethylsulfonium halide, halogenation, amination.