1,5-二甲氧基-3-甲基-2-硝基苯 | 27508-87-8

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 中文名称: 1,5-二甲氧基-3-甲基-2-硝基苯
• 英文名称: 3,5-Dimethoxy-2-nitro-toluol
• 英文别名: 1,5-Dimethoxy-3-methyl-2-nitrobenzene
• CAS: 27508-87-8
• 化学式: C₉H₁₁NO₄
• 分子量: 197.191
• InChiKey: GRNKAWLLLBFVTO-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.1
• 重原子数：
  14
• 可旋转键数：
  2
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.33
• 拓扑面积：
  64.3
• 氢给体数：
  0
• 氢受体数：
  4

反应信息

• 作为反应物：
  描述：

  1,5-二甲氧基-3-甲基-2-硝基苯 在 三溴化硼 作用下， 以 二氯甲烷 为溶剂， 反应 1.0h， 以97%的产率得到5-methoxy-3-methyl-2-nitrophenol
  参考文献：
  名称：

  Analogs of the cyclic hydroxamic acid 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3-one (DIMBOA): decomposition to benzoxazolinones and reaction with .beta.-mercaptoethanol

  摘要：

  Analogues of the aglucones of naturally occurring cyclic hydroxamic acids (2,4-dihydroxy-1,4-benzoxazin-3-ones) from Gramineae (Poaceae) have been synthesized by the reductive cyclization of the ring-substituted methyl alpha-(o-nitrophenoxy)-alpha-methoxyacetates, followed by demethylation of the C-2 methoxy group with BBr3 or BCl3 to reveal the 2-hydroxy group. A structure-activity series was produced by varying the substituent at C-7 on the aromatic ring [R = MeO (1), t-Bu (6), Me (7), H (8), Cl (9), F (10), CO2Me (11a)]. The pK(a) values for the hydroxamic acid and the phenol moieties were determined for each member of the C-7 series. They correlated well with sigma in a linear free energy relationship (LFER) yielding values of rho = 0.71 (with sigma-p) for pK(a1) (the hydroxamic acid) and rho = 1.6 (with sigma-m) for pK(a2) (the phenol). A LFER also existed between the rate constants for the unimolecular decomposition of these hydroxamic acids to benzoxazolinones and sigma+ (rho = 1.1). The rates of hydroxamic acid reduction to lactams by beta-mercaptoethanol were also investigated. It was found that only compounds with electron-rich aromatic rings and specifically an oxa functionality para to the hydroxamic acid nitrogen atom (compounds 1 and 3-5) had measurable rates of reduction. H-1 NMR spectra recorded during this reaction in D2O buffers (pD9), however, showed that compounds 1, 2, 6-9 (the only ones investigated) formed a hemithioacetal at C-2 even though only 1 has a measurable rate of reduction by the same thiol. The remarkable rate enhancement provided by an oxa functionality suggests that reduction occurs by direct attack of thiolate on the hydroxamic nitrogen of a resonance-stabilized ion pair.

  DOI：

  10.1021/jo00005a025
• 作为产物：
  描述：

  3,5-二甲氧基甲苯 在 硝酸 作用下， 生成 1,5-二甲氧基-3-甲基-2-硝基苯
  参考文献：
  名称：

  亲电芳族取代。第22部分。甲磺酸中某些反应性芳族化合物的硝化，以及取代萘和1,2-二苯乙烷的相遇率硝化中的位置选择性问题

  摘要：

  甲烷磺酸水溶液中的硝化反应通过速率常数对酸度的依赖性，对芳香族化合物浓度的动力学形式为零阶的识别，以及极限速率常数的存在来确定，该速率常数被确定为相遇速率常数。涉及硝基离子。

  DOI：

  10.1039/p29790000747

文献信息

• Analogs of the cyclic hydroxamic acid 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3-one (DIMBOA): decomposition to benzoxazolinones and reaction with .beta.-mercaptoethanol
  作者：Jeffrey Atkinson、Peter Morand、John T. Arnason、Hermann M. Niemeyer、Hector R. Bravo

  DOI：10.1021/jo00005a025

  日期：1991.3

  Analogues of the aglucones of naturally occurring cyclic hydroxamic acids (2,4-dihydroxy-1,4-benzoxazin-3-ones) from Gramineae (Poaceae) have been synthesized by the reductive cyclization of the ring-substituted methyl alpha-(o-nitrophenoxy)-alpha-methoxyacetates, followed by demethylation of the C-2 methoxy group with BBr3 or BCl3 to reveal the 2-hydroxy group. A structure-activity series was produced by varying the substituent at C-7 on the aromatic ring [R = MeO (1), t-Bu (6), Me (7), H (8), Cl (9), F (10), CO2Me (11a)]. The pK(a) values for the hydroxamic acid and the phenol moieties were determined for each member of the C-7 series. They correlated well with sigma in a linear free energy relationship (LFER) yielding values of rho = 0.71 (with sigma-p) for pK(a1) (the hydroxamic acid) and rho = 1.6 (with sigma-m) for pK(a2) (the phenol). A LFER also existed between the rate constants for the unimolecular decomposition of these hydroxamic acids to benzoxazolinones and sigma+ (rho = 1.1). The rates of hydroxamic acid reduction to lactams by beta-mercaptoethanol were also investigated. It was found that only compounds with electron-rich aromatic rings and specifically an oxa functionality para to the hydroxamic acid nitrogen atom (compounds 1 and 3-5) had measurable rates of reduction. H-1 NMR spectra recorded during this reaction in D2O buffers (pD9), however, showed that compounds 1, 2, 6-9 (the only ones investigated) formed a hemithioacetal at C-2 even though only 1 has a measurable rate of reduction by the same thiol. The remarkable rate enhancement provided by an oxa functionality suggests that reduction occurs by direct attack of thiolate on the hydroxamic nitrogen of a resonance-stabilized ion pair.
• Musso, Chemische Berichte, 1958, vol. 91, p. 349,358
  作者：Musso

  DOI：——

  日期：——
• Electrophilic aromatic substitution. Part 22. The nitration of some reactive aromatics in methanesulphonic acid, and the question of positional selectivity in encounter rate nitrations of substituted naphthalenes and 1,2-diphenylethanes
  作者：James W. Barnett、Roy B. Moodie、Kenneth Schofield、Peter G. Taylor、John B. Weston

  DOI：10.1039/p29790000747

  日期：——

  Nitrations in aqueous methanesulphonic acid are shown by the steep acidity dependence of the rate constants, the identification of a kinetic form zeroth-order in the concentration of the aromatic, and the existence of a limiting rate constant identified as the encounter rate constant, most probably to involve the nitronium ion.

  甲烷磺酸水溶液中的硝化反应通过速率常数对酸度的依赖性，对芳香族化合物浓度的动力学形式为零阶的识别，以及极限速率常数的存在来确定，该速率常数被确定为相遇速率常数。涉及硝基离子。
• Synthesis and structure–activity relationship of 3-arylbenzoxazines as selective estrogen receptor β agonists
  作者：Wu Yang、Yufeng Wang、Zhengping Ma、Rajasree Golla、Terry Stouch、Ramakrishna Seethala、Susan Johnson、Rong Zhou、Timur Güngör、Jean H.M Feyen、John K Dickson

  DOI：10.1016/j.bmcl.2004.01.099

  日期：2004.5

  A series of 3-aryl-7-hydroxybenzoxazine analogues have been prepared and evaluated as ligands for the two estrogen receptor subtypes (ERalpha and ERbeta). From the radioligand binding assay, compounds with more than a 10-fold binding selectivity toward the ERbeta subtype have been identified. These compounds have also been shown to be potent full agonists in the functional assay by activation of ERE promoted transcription, with the best compound being 20-fold more potent than genistein. (C) 2004 Elsevier Ltd. All rights reserved.