1-溴-4-甲氧基-2,3,5,6-四甲基-苯 | 56474-57-8

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯酚醚
• 中文名称: 1-溴-4-甲氧基-2,3,5,6-四甲基-苯
• 英文名称: 4-Bromo-2,3,5,6-tetramethylanisole
• 英文别名: Bromdurenol-methylether；4-Brom-2.3.5.6-tetramethylanisol；1-Bromo-4-methoxy-2,3,5,6-tetramethylbenzene
• CAS: 56474-57-8
• 化学式: C₁₁H₁₅BrO
• 分子量: 243.143
• InChiKey: CALWRWLFQOSHNJ-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4
• 重原子数：
  13
• 可旋转键数：
  1
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.45
• 拓扑面积：
  9.2
• 氢给体数：
  0
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  1-溴-4-甲氧基-2,3,5,6-四甲基-苯 在 正丁基锂 、 硼酸三异丙酯 、 盐酸 作用下， 以 四氢呋喃 、 环己烷 、 水 为溶剂， 反应 1.0h， 以55%的产率得到(4-methoxy-2,3,5,6-tetramethyl)-phenyl boronic acid
  参考文献：
  名称：

  Syntheses of extreme sterically hindered 4-methoxyboronic acids

  摘要：

  4-Iodoanisoles 3a,b, 3d and 4-bromoanisoles 4a-d were readily obtained. An extreme steric hindrance precluded obtaining 3c. Catalytic borylation of 3a,b, 3d followed by hydrolysis of boronic ester 26a,b, 26d easily provided the boronic acids 5a,b, 5d. Compounds Sa and 5d were also synthesised, starting from 4a and 4d, by halogen/metal exchange. Because of a too important steric hindrance, this last reaction failed with 4c and 4b led to the unexpected but stable boronic ester 6. The final obtaining of 5b required a strongly basic hydrolysis with heating. (C) 2009 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.tet.2009.11.103
• 作为产物：
  描述：

  2,3,5,6-tetramethylanisole 在 N-溴代丁二酰亚胺(NBS) 作用下， 以 乙腈 为溶剂， 以98%的产率得到1-溴-4-甲氧基-2,3,5,6-四甲基-苯
  参考文献：
  名称：

  Syntheses of extreme sterically hindered 4-methoxyboronic acids

  摘要：

  4-Iodoanisoles 3a,b, 3d and 4-bromoanisoles 4a-d were readily obtained. An extreme steric hindrance precluded obtaining 3c. Catalytic borylation of 3a,b, 3d followed by hydrolysis of boronic ester 26a,b, 26d easily provided the boronic acids 5a,b, 5d. Compounds Sa and 5d were also synthesised, starting from 4a and 4d, by halogen/metal exchange. Because of a too important steric hindrance, this last reaction failed with 4c and 4b led to the unexpected but stable boronic ester 6. The final obtaining of 5b required a strongly basic hydrolysis with heating. (C) 2009 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.tet.2009.11.103

文献信息

• Nuclear versus Side-Chain Bromination of Methyl-Substituted Anisoles by N-Bromosuccinimide
  作者：Gert-Jan M. Gruter、Otto S. Akkerman、Friedrich Bickelhaupt

  DOI：10.1021/jo00095a023

  日期：1994.8

  The reactions of methyl-substituted anisoles with N-bromosuccinimide in CCl4 are reported. In the absence of a catalyst and under irradiation, some of these substrates undergo nuclear bromination in competition with the well-known side-chain bromination. With 2-methylanisole and with 2,6-dimethylanisole, nuclear bromination is not observed, whereas with 3,5-dimethylanisole, nuclear bromination at the 4-position is the dominating reaction. Investigation of the reactivity of several other methyl-substituted anisoles revealed the following general trend: methyl-substituted anisoles are attacked at the position para to the methoxy group rather than at the side chain when (at least) two methyl groups are present at positions 3 and 5. When positions 2 and 6 are both occupied, nuclear bromination is retarded; in 2,6-dimethylanisole and in 2,3,6-trimethylanisole, only side-chain bromination is observed. In contrast, in 2,3,5,6-tetramethylanisole, the 4-position is sufficiently reactive to be brominated, because the decrease in reactivity by the presence of two methyl groups at positions 2 and 6 is overruled by the two additional methyl groups at positions 3 and 5; as a result, both nuclear and side-chain bromination occur. The observed chemospecificity can be rationalized by a difference in mechanism: the side-chain bromination is a radical reaction, while the nuclear bromination is an electrophilic aromatic substitution reaction, which is so far contrary to expectation, as irradiation had been expected to favor radical processes.
• Kamshii,L.P. et al., Journal of Organic Chemistry USSR (English Translation), 1977, vol. 13, p. 740 - 746
  作者：Kamshii,L.P. et al.

  DOI：——

  日期：——
• Gruter Gert-Jan M., Akkerman Otto S., Bickelhaupt Friedrich, J. Org. Chem, 59 (1994) N 16, S 4473- 4481
  作者：Gruter Gert-Jan M., Akkerman Otto S., Bickelhaupt Friedrich

  DOI：——

  日期：——
• US4025633A
  申请人：——

  公开号：US4025633A

  公开（公告）日：1977-05-24
• US4361573A
  申请人：——

  公开号：US4361573A

  公开（公告）日：1982-11-30