| 查看: 899 | 回复: 1 | ||
[求助]
求醇羟基溴代反应的文献，注意是普通的醇羟基，谢谢！ 已有1人参与
|
| 求醇羟基溴代反应的文献，注意是普通的醇羟基，谢谢！ |
回复此楼» 猜你喜欢
高温高压反应求助
已经有4人回复
-
药学B区求调剂
已经有4人回复
-
药物学论文润色/翻译怎么收费?
已经有110人回复
-
重庆医科大学-人工智能医学学院
已经有0人回复
-
重庆医科大学-人工智能医学学院
已经有1人回复
-
可能上不了岸？有条件的可以考虑其他出路
已经有0人回复
-
丽水学院材料与能源工程学院招收调剂！（可调剂专业范围广）
已经有0人回复
-
晴川万里新书
已经有4人回复
-
分子对接相关经验分享
已经有0人回复
-
分子对接相关经验分享
已经有0人回复
-
在线求助，急！！！请问哪里可以做磁性纳米材料的高分辨透射电镜的测试表征呀？
已经有3人回复
» 本主题相关价值贴推荐，对您同样有帮助:
- 羟基，和2-溴丙酰溴反应问题
已经有30人回复
- 醇羟基的被取代反应
已经有8人回复
- 碘取代醇羟基，怎么做？
已经有12人回复
- TsCl与醇羟基的反应
已经有18人回复
- 苄溴和羟基反应
已经有8人回复
- NN-二甲基乙醇胺的羟基和溴代苯能否发生反应
已经有12人回复
- 碱性条件下环氧基团（环氧树脂）与醇羟基反应机理的文献
已经有4人回复
- 醇羟基和酚羟基的醚化，酯化反应
已经有4人回复
- 在什么条件下异氰酸酯只跟醇羟基反应不跟羧羟基反应
已经有17人回复
- 对羟基苄醇 到 对羟基苄氯反应中的问题
已经有10人回复
- 求助醇羟基和氯代亚磷酸二酯的反应？
已经有3人回复
- 长链带支链烷烃伯醇上的醇羟基怎么被溴取代
已经有7人回复
- 醇羟基怎么进行反应，变成带有氨基的基团？会跟三乙胺发生反应吗？
已经有15人回复
- 环氧树脂与羟基反应的条件，谢谢关注
已经有20人回复
- 羟基聚合物与2-溴代异丁酰溴反应，是不是酰溴加入后，溶液会变成血红色？
已经有26人回复
- 有关 醇羟基 氢原子离去问题
已经有7人回复
- 求羟基变为醚的反应
已经有13人回复
- 有关三氟甲磺酸酐与醇羟基的反应
已经有24人回复
- 【求助】羟基溴代
已经有14人回复
- 【求助】怎样把烷烃上的羟基变为溴
已经有21人回复
- 【求助】醇羟基与TSCl、MSCl、(MS)2O反应的问题
已经有5人回复
- 【求助】醇羟基脱保护
已经有7人回复
xujun9998
版主 (著名写手)
- 应助: 352 (硕士)
- 贵宾: 0.964
- 金币: 24367.2
- 散金: 2050
- 红花: 34
- 帖子: 2031
- 在线: 762小时
- 虫号: 121124
- 注册: 2005-12-03
- 性别: GG
- 专业: 有机合成
- 管辖: 有机资源
【答案】应助回帖
感谢参与，应助指数 +1
|
CBr4–Ph3P is very straightforward and widely used. Workup and purification can be messy at times because of the by-product, Ph3PO. To a mixture of the alcohol (0.800 g, 3.36 mmol) and carbon tetrabromide (1.337 g,4.03 mmol) in CH2Cl2 at 0 ºC was added a solution of PPh3 (1.319 g, 5.03 mmol) in CH2Cl2 (3 mL). The reaction mixture was stirred at room temperature for 1 h, concentrated under reduced pressure, and purified by column chromatography to afford the bromide (0.941 g, 93% yield). Reference: Hu, T.-S.; Yu, Q.; Wu,Y.-L.; Wu,Y. J. Org. Chem. 2001, 66, 853–861. A two-step sequence consisting of mesylate formation followed by treatment with LiBr can also be used. This procedure involves two steps, but workup and purification are very straightforward. The bromide can be carried out to the next step without further purification in many cases. To a solution of 5-hydroxymethyl-1-methylcyclopentene (3.8 g, 34 mmol) in CH2Cl2(50 mL) at 0 ºC was added triethylamine (5.2 mL, 37 mmol) followed by methanesulfonyl chloride (2.9 mL, 37 mmol). The mixture was stirred at 0 ºC for 5 h and then water was added. The organic layer was separated and the aqueous layer was extracted with ether. The combined organic extracts were dried over MgSO4 and the solvent was removed under reduced pressure to give 6.4 g (98%) of (2-methylcyclopent-2-enyl)methyl methanesulfonate, which was used in the next step without further purification. A solution containing the mesylate (6.4 g, 34 mmol) in acetone (70 mL) was treated with lithium bromide (8.89 g, 102 mmol). The mixture was heated at reflux for 6 h, cooled to room temperature, diluted with water, extracted with ether, and the combined ethereal extracts were dried over MgSO4. Removal of the solvent under reduced pressure gave 4.6 g (78%) of 5-bromomethyl-1-methylcyclopentene, which was used in the next step without further purification. Reference: Padwa, A.; Dimitroff, M.; Liu, B. Org. Lett. 2000, 2, 3233–3235. |
2楼2015-01-05 09:04:48
30