(+/-)-2-(4-methoxyphenyl)-3-methyl-[2R,3R]-2,3-dihydrobenzo[b]furan-5-ol

• 分子结构分类: 有机化合物 - 苯丙烷和聚酮 - 2-芳基苯并呋喃类黄酮
• 英文名称: (+/-)-2-(4-methoxyphenyl)-3-methyl-[2R,3R]-2,3-dihydrobenzo[b]furan-5-ol
• 英文别名: 2-(4-methoxyphenyl)-3-methyl-2,3-dihydrobenzofuran-5-ol；(2S,3S)-2-(4-methoxyphenyl)-3-methyl-2,3-dihydro-1-benzofuran-5-ol
• 化学式: C₁₆H₁₆O₃
• 分子量: 256.301
• InChiKey: HWTUSTIHWQFOIN-QFYYESIMSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.4
• 重原子数：
  19
• 可旋转键数：
  2
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.25
• 拓扑面积：
  38.7
• 氢给体数：
  1
• 氢受体数：
  3

反应信息

• 作为反应物：
  描述：

  (+/-)-2-(4-methoxyphenyl)-3-methyl-[2R,3R]-2,3-dihydrobenzo[b]furan-5-ol 在 吡啶 、 四(三苯基膦)钯 、 potassium carbonate 作用下， 以 乙醇 、 水 、 1,2-二氯乙烷 、 甲苯 为溶剂， 反应 19.0h， 生成 (4-methoxyphenyl)-3-methyl-5-((E)-prop-1-en-1-yl)-2,3-dihydrobenzofuran
  参考文献：
  名称：

  用于 2,3-二氢苯并呋喃可见光光合作用的定制 COF

  摘要：

  多相光催化被认为是解决能源和环境持续问题的一种生态友好和可持续的方法。最近，基于共价有机骨架（COFs）的多相光催化剂因其在光催化有机转化中的卓越性能和可回收性而受到广泛关注，为基于贵金属/有机染料的均相光催化剂提供了一种有前途的替代方案。在此，我们报告了Hex-Aza-COF-3作为一种无金属、可见光激活和可重复使用的多相光催化剂，用于合成 2,3-二氢苯并呋喃，作为一种药学相关的结构基序，通过酚类与烯烃的选择性氧化 [3+2] 环加成反应。此外，我们证明了通过 [3+2] 环加成反应合成天然产物 (±)-conocarpan 和 (±)-紫檀素是使用Hex-Aza-COF-3作为多相光催化剂的重要步骤。有趣的是，吩嗪和六氮杂苯并菲作为刚性杂环单元存在于Hex-Aza-COF-3中加强共价键，增强可见光区的吸收，并缩小能带，导致光催化反应中优异的活性、电荷传输、稳定性和可回收性，这从超快

  DOI：

  10.1021/jacs.2c10471
• 作为产物：
  描述：

  茴香烯 在 ammonium peroxydisulfate 、 tris(2,2′-bipyrazine-N1,N1′)ruthenium(II) hexafluorophosphate 、 palladium 10% on activated carbon 、 氢气 作用下， 以 四氢呋喃 、 乙腈 为溶剂， 反应 30.5h， 生成 (+/-)-2-(4-methoxyphenyl)-3-methyl-[2R,3R]-2,3-dihydrobenzo[b]furan-5-ol
  参考文献：
  名称：

  苯酚氧化[3+2]环加成光催化合成二氢苯并呋喃

  摘要：

  我们报告了苯酚和烯烃的氧化[3+2]环加成反应方案，适用于一大类二氢苯并呋喃天然产物的模块化合成。可见光激活的过渡金属光催化使得过硫酸铵成为一种易于处理的良性末端氧化剂。很容易被光氧化还原催化氧化的有机底物范围广泛，表明该策略可能适用于各种有用的氧化转化。

  DOI：

  10.1002/anie.201406393

文献信息

• InCl₃-Catalyzed [3 + 2] CycloadditionReactions: A Facile Synthesis of<i>trans</i>-Dihydrobenzofuransand Substituted Cyclobutane Derivatives
  作者：J. S. Yadav、B. V. Reddy、G. Kondaji

  DOI：10.1055/s-2003-39175

  日期：——

  1,4-Benzoquinones undergo smoothly [3 + 2] cycloaddition reactions with electron rich alkenes in the presence of 10 mol% indium trichloride or 5 mol% iodine under mild conditions to afford the corresponding 2,3-dihydrobenzofurans in excellent yields with trans-selectivity. Similarly, methyl vinyl ketone reacts with electron rich olefins to produce substituited trans-cyclobutane derivatives.

  在温和条件下，1,4-苯醌与富电子烯烃在 10 mol% 三氯化铟或 5 mol% 碘存在下顺利进行 [3 + 2] 环加成反应，以优异的产率得到相应的 2,3-二氢苯并呋喃和反式-选择性。类似地，甲基乙烯基酮与富电子烯烃反应生成取代的反式-环丁烷衍生物。
• Cycloaddition of styrene derivatives with quinone catalyzed by ferric ion; remarkable acceleration in an ionic liquid solvent system
  作者：Hiroyuki Ohara、Hiromi Kiyokane、Toshiyuki Itoh

  DOI：10.1016/s0040-4039(02)00405-7

  日期：2002.4

  Ferric ion-catalyzed cycloaddition of styrene derivatives with quinone gave 2,3-dihydrobenzofuran derivatives in excellent yields with trans selectivity; remarkable acceleration was observed when the reaction was carried out in an ionic liquid solvent system.

  苯乙烯衍生物与醌的铁离子催化环加成反应，可得到高收率的反式选择性的2,3-二氢苯并呋喃衍生物。当反应在离子液体溶剂体系中进行时，观察到明显的加速。
• Stereoselective 3 + 2 and stereospecific 2 + 2 cycloaddition reactions of alkenes and quinones
  作者：Thomas A. Engler、Keith D. Combrink、James E. Ray

  DOI：10.1021/ja00231a084

  日期：1988.11

  mM NaCl and 25 mM tris-acetate at pH 7.0.14 After 0.5 h incubation at 24 OC, 4 mM dithiothreitol was added to initiate strand cleavage. The reaction was allowed to continue for 6 h (24 "C). The double strand cleavage products were separated on a 0.4% vertical agarose gel which resolves DNA segments up to 25 kbp in size (Figure 3). Therefore, DNA uniquely labeled at the R and

  pH 7.0.14 的 mM NaCl 和 25 mM tris-乙酸盐 在 24 ℃下孵育 0.5 小时后，加入 4 mM 二硫苏糖醇以启动链裂解。使反应持续 6 小时（24°C）。双链切割产物在 0.4% 垂直琼脂糖凝胶上分离，该凝胶可解析大小高达 25 kbp 的 DNA 片段（图 3）。因此，DNA 在R 和
• Stereospecific Lewis Acid-Promoted Reactions of Styrenyl Systems with 2-Alkoxy-(6-Alkyl)-1,4-Benzoquinones: Scope, Limitations, and Synthetic Applications
  作者：Thomas A. Engler、Keith D. Combrink、Michael A. Letavic、Kenneth O. Lynch、James E. Ray

  DOI：10.1021/jo00101a016

  日期：1994.11

  Titanium(IV)-promoted reactions of various (E)-1-propenylbenzenes with 2-methoxy- and 2-methoxy-6-methyl-1,4-benzoquinones produce trans 2-aryl-6-methoxy-3-(and 4-di)methyl-2,3-dihydro-5-benzofuranols (10-12), rel-(1S,6R,7R,8R)-3-methoxy-8-aryl-7-(and 1-di)methylbicyclo[4.2.0]oct-3-ene-2,5-diones (2 + 2 cycloadducts, 13-15) and/or rel-(1R,5R,6R,7R)-7-aryl-3-hydroxy-6-(and 4)methylbicyclo[3.2.1]oct-3-ene-2,8-diones (5 + 2 cycloadducts, 16/17). In many cases, each of the three products can be obtained selectively in good yield by control of reaction conditions and/or by choice of substituents on the quinone or the propenylbenzene. The dihydrobenzofurans are formed stereoselectively, whereas the formation of the bicyclo[4.2.0] systems are stereospecific processes. Thus, reactions of (Z)-1-propenylbenzenes afford rel-(1R,6S,7R,8R)-8-aryl-3-methoxy-7-methylbicyclo[4.2.0]oct-3-ene-2,5-diones (24, 25). No bicyclo[3.2.1]systems. are found in reactions of the (Z)-propenylbenzenes. The products all apparently result from a thermally allowed 2 pi + 4 pi (2 + 5) cycloaddition of the propenylbenzene with a 2-methoxy-4-oxo-2,5-cyclohexadienyl carbocation intermediate (26) formed by coordination of the Ti(IV) to the C-1 carbonyl oxygen of the quinone. In the cycloaddition, the aryl ring of the propenylbenzene occupies an endo position with respect to the pentadienyl carbocation moiety of 26 and the bicyclo[3.2.1] carbocation product of the cycloaddition (28/29) either undergoes dealkylation or rearrangment to yield the observed products. Treatment of the bicylo[4.2.0] systems with protic acid effects their rearrangement to the dihydrobenzofuranols. Reactions of 2-propenylbenzenes and arylcycloalkenes with the quinones regioselectively give dihydrobenzofuranols 43-45 and 49-54, respectively; a 2 + 2 cycloadduct is found in low yield in only one case. The 7-aryl-3-hydroxy-6-methylbicyclo[3.2.1]oct-3-ene-2,8-diones are produced exclusively in reactions of 2-((4-methoxybenzyl)oxy)-1,4-benzoquinones with various propenylbenzenes. Application of these reactions to the synthesis of (+/-)-obtusafuran, (+/-)-liliflol-B, (+/-)-kadsurenone, and (+/-) denudatin are reported.
• Development of Solvent-Driven Iron-Catalyzed Reactions
  作者：Toshiyuki Itoh

  DOI：10.3987/rev-16-842

  日期：——

  The possibility of solvent-driven iron-catalyzed reactions has been investigated using ionic liquids and acetonitrile as key solvents. Three iron-catalyzed reactions, the intramolecular cyclization of cyclopropane dithioacetals, the [2+2]-cycloaddition of (trans)-anethole, and the [2+3]-type cycloaddition of styrene derivatives with 1,4-benzoquinone, were first developed using acetonitrile as solvent in the presence of 3 similar to 5 mol% of Fe(ClO4)(3)center dot Al2O3 or Fe(BF4)(2)center dot 6H(2)O under air conditions. In particular, we found the rapid cycloaddition of iron-catalyzed [2+3]-type cycloaddition of styrene derivatives with 1,4-benzoquinone when the reaction was carried out in an ionic liquid which contained [PF6] or [Tf2N] anion. Homo-coupling reaction of aryl or alkynyl Grignard reagent was next discovered using 1 mol% of FeCl3 as catalyst and the reaction also proceeded very rapidly in an ionic liquid. We also found that 3-5 mol% of Fe(ClO4)(2)center dot Al2O3 or Fe(BF4)(2)center dot 6H(2)O-successfully catalyzed Friedel-Crafts type alkylation of indoles or pyrroles with vinyl ketones or alpha-aryl-beta-silylalcohol. In particular, the reaction of chiral alpha-aryl-beta-silylalcohol with indole using Fe(ClO4)(3)center dot nH(2)O as catalyst proceeded with retention of the configuration of stereochemistry of the hydroxyl group. Then, we discovered the first example of iron-catalyzed enantioselective C-S bond formation via Michael addition of thiols to (E)-3-crotonoyloxazolidin-2-one using 10 mol% of Fe(BF4)(2)/Pybox. We further demonstrated that Fe(ClO4)(3)center dot Al2O3-catalyzed the Nazarov type cyclizations of thiophene, pyrrole, indole, benzofuran, and benzo[b]thiophene derivatives using ionic liquids as solvent. Solvents have been recognized as a by-player in chemical reactions in the process of "optimization of reaction conditions". However, further investigation of the solvent-driven iron-catalyzed reaction will allow discovery of useful reactions for organic syntheses.