5,6-bis(methoxycarbonyl)benzothiazole | 185145-61-3

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 苯并噻唑类
• 英文名称: 5,6-bis(methoxycarbonyl)benzothiazole
• 英文别名: 5,6-Benzothiazoledicarboxylic acid, dimethyl ester；dimethyl 1,3-benzothiazole-5,6-dicarboxylate
• CAS: 185145-61-3
• 化学式: C₁₁H₉NO₄S
• 分子量: 251.263
• InChiKey: FSTYTUVOINDNGZ-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.1
• 重原子数：
  17
• 可旋转键数：
  4
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.18
• 拓扑面积：
  93.7
• 氢给体数：
  0
• 氢受体数：
  6

反应信息

• 作为产物：
  描述：

  丁炔二酸二甲酯 、 4-(bromomethyl)-5-(dibromomethyl)-1,3-thiazole 在 sodium iodide 作用下， 以 N,N-二甲基甲酰胺 为溶剂， 反应 2.5h， 以56%的产率得到5,6-bis(methoxycarbonyl)benzothiazole
  参考文献：
  名称：

  Generation and Trapping of 4-Methylene-5-(bromomethylene)-4,5-dihydrothiazole with Dienophiles

  摘要：

  4-(Bromomethyl)-5-(dibromomethyl)thiazole (1) was prepared in good yields by bromination of 4,5-dimethylthiazole with 3.3 equiv of NBS in the presence of AIBN. Treatment of 1 with sodium iodide led to a thiazole o-quinodimethane 2 which was trapped in situ with dienophiles such as N-phenylmaleimide, DMAD, or acrylate derivatives. From the latter, 6-substituted-4,5-dihydrobenzothiazoles 7 are selectively formed. Anthra[2,3-b]thiazole-4,5-diones 13-15 were obtained from naphthoquinones. With 2- or 3-bromonaphthoquinones (11 or 12), the cycloadditions were found highly regioselective. Structural assignment of the regioisomers was made by a 2D H-1-C-13 HMBC technique performed on the aromatized cycloadduct 15b. Calculations of HOMO and LUMO frontier orbital coefficients by the semiempirical PM3 method show that the regiochemistry observed in the cycloadditions of 2 toward acrylate dienophiles or naphthoquinones 11 and 12 did not agree with the corresponding values.

  DOI：

  10.1021/jo961457n

文献信息

• Generation and Diels-Alder Trapping of 4,5-Bis(bromomethylene)-4,5-dihydrothiazole
  作者：Karine Jouve、Félix Pautet、Monique Domard、Houda Fillion

  DOI：10.1002/(sici)1099-0690(199809)1998:9<2047::aid-ejoc2047>3.0.co;2-z

  日期：1998.9

  Treatment of 4,5-bis(dibromomethyl)thiazole (1a) with sodium iodide in DMF led to 4,5-bis(bromomethylene)-4,5-dihydrothiazole (2a). Trapping the latter in situ with dienophiles afforded directly the aromatized cycloadducts. Starting with 5-hydroxynaphthoquinone or its 2- and 3-bromo derivatives 6 gave a mixture of the tetracyclic quinones 10 + 11 from which the 1,6-regioisomer 10 predominates. Using

  在DMF中用碘化钠处理4,5-双（二溴甲基）噻唑（1a），得到4,5-双（溴亚甲基）-4,5-二氢噻唑（2a）。用亲二烯体原位捕获后者，直接得到芳构化的加合物。从5-羟基萘醌或其2-和3-溴衍生物6开始，得到四环醌10 + 11的混合物，其中以1，6-区域异构体10为主。使用丙烯酸二烯酯，得到6-取代的苯并噻唑13作为主要产物。2a和萘醌6之间的环加成反应的区域化学符合前沿分子轨道理论的预测。相比之下，从2a和丙烯酸酯二烯键体12观察到的区域选择性与先前使用5-溴亚甲基-4-亚甲基-4,5-二氢噻唑（2b）所获得的相似，与预测的相反，可以通过竞争性迈克尔更好地适应。添加，然后进行环化消除步骤。
• Generation of a Thiazole o-Quinodimethane from an Imino Derivative and Its Intermolecular Diels-Alder Trapping with Alkynes or Quinoes.
  作者：Karine JOUVE、Felix PAUTET、Monique DOMARD、Houda FILLION

  DOI：10.1248/cpb.47.1064

  日期：——

  (E)-5-(N-Benzylformimidoyl)-4-methylthiazole 3 was prepared in good yield from 5-formyl-4-methylthiazole and benzylamine. Treatment of 3 with methylchloroformate in the presence of ethyldiisopropylamine in refluxing toluene has generated o-quinodimethane (o-QDM) 4. In situ trapping of the latter with acetylenic or quinonoid dienophiles directly afforded the aromatized products 5, 6, 7 and 9. An unprecedented elimination of N-car-bomethoxybenzylamine occurred from the primary dihydro or tetrahydro cycloadducts. Starting from ethyl-propynoate or juglone 8a, the single regioisomer 6 or 9a was obtained, while when using 2- or 3-bromojuglone 8b or 8c the reaction regiospecifically gave 9a or 9b. Calculations by the semi-empirical method PM3 indicated that the regiochemistry observed connot be predicted by the frontier orbital coefficients theory for a concerted electrocyclic reaction, but is better explained by an attack of the nucleophilic end of diene 4 on the more electron deficient carbon of the dienophiles.

  由5-甲酰基-4-甲基噻唑和苄胺以良好的产率制备(E)-5-(N-苄基甲亚胺酰基)-4-甲基噻唑3。在回流甲苯中，在乙基二异丙胺存在下，用氯甲酸甲酯处理 3，生成邻醌二甲烷 (o-QDM) 4。后者用炔属或醌型亲二烯体原位捕获，直接得到芳构化产物 5、6、7 和 9。 N-羧基甲氧基苄胺从初级二氢或四氢环加合物中发生了前所未有的消除。从丙炔酸乙酯或胡桃酮8a开始，获得单一区域异构体6或9a，而当使用2-或3-溴胡桃酮8b或8c时，反应区域特异性地产生9a或9b。半经验方法 PM3 的计算表明，观察到的区域化学不能通过协同电环反应的前沿轨道系数理论来预测，但可以通过二烯 4 的亲核末端对更缺电子的碳的攻击来更好地解释。亲二烯体。