3-[2,4-Bis(methoxymethoxy)phenyl]-4-(bromomethyl)-7-(methoxymethoxy)-2H-1-benzopyran-2-one | 883558-13-2

• 分子结构分类: 有机化合物 - 苯丙烷和聚酮 - 异黄酮类化合物
• 英文名称: 3-[2,4-Bis(methoxymethoxy)phenyl]-4-(bromomethyl)-7-(methoxymethoxy)-2H-1-benzopyran-2-one
• 英文别名: 3-[2,4-bis(methoxymethoxy)phenyl]-4-(bromomethyl)-7-(methoxymethoxy)chromen-2-one
• CAS: 883558-13-2
• 化学式: C₂₂H₂₃BrO₈
• 分子量: 495.324
• InChiKey: YGMYPBITBVXYBL-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.4
• 重原子数：
  31
• 可旋转键数：
  11
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.32
• 拓扑面积：
  81.7
• 氢给体数：
  0
• 氢受体数：
  8

反应信息

• 作为产物：
  描述：

  4-methyl-3-(2,4-dihydroxyphenyl)-7-hydroxycoumarin 在 potassium carbonate 、 lithium hexamethyldisilazane 作用下， 以 四氢呋喃 为溶剂， 反应 5.0h， 生成 3-[2,4-Bis(methoxymethoxy)phenyl]-4-(bromomethyl)-7-(methoxymethoxy)-2H-1-benzopyran-2-one 、
  参考文献：
  名称：

  Development of a Scalable Synthetic Process for Selective Bromination of 4-Methyl-3,7-Substituted Coumarins

  摘要：

  The hydroxyl-protected coumarin derivatives 6a-e of 4-methyl3-(2,4-dihydroxyphenyl)-7-hydroxycoumarin (4) are key intermediates in the synthesis of unsymmetrical benzopyranobenzopyran compounds, a novel series of selective estrogen receptor modulators (SERMs). Free radical bromination of the 4-methyl group on 7-acetoxy-3-[(2,4-diacetoxy)phenyl]-4-methylcoumarin (6a) with NBS resulted in incomplete reactions and low to moderate yields (25-44%) of 4-bromomethyl product 7a. Lithiation of the 4-methyl group of coumarins 6b (R = SEM), 6c (R = MOM) and 6d (R = Bz) with LDA (1.1 - 1.7 equiv) or LHMDS (1.2-1.7 equiv) generated carbanion in THF at -76 degrees C, which was quenched with bromine (1.5-2.0 equiv) to afford 4-bromomethyl derivatives 7b-d in good yields (80-90%) in small scale reactions (2-20 g). The reaction yields declined to similar to 70% when the scale was increased to >= 80 g. Furthermore, treatment of 3-[(2,4-dimethoxy)phenyl]-7-methoxy-4-methylcoumarin (6e) with LHMDS (1.08 equiv) in THF followed by rapid inverse quenched with NBS (1.10 equiv) in THF at -76 degrees C, selectively produced the desired 4-bromomethyl compound 7e in excellent yield (> 90%) in both small (2-8 g) and large (80-150 g) scale reactions. A non-chromatographic process was developed to prepare 6e. This selective and efficient procedure was successfully transferred to the pilot plant to produce multikilograms of 4-bromomethyl coumarin 7e.

  DOI：

  10.1021/op050242p

文献信息

• Development of a Scalable Synthetic Process for Selective Bromination of 4-Methyl-3,7-Substituted Coumarins
  作者：Xun Li、Nareshkumar Jain、Ronald K. Russell、Robert Ma、Shawn Branum、Jiayi Xu、Zhihua Sui

  DOI：10.1021/op050242p

  日期：2006.3.1

  The hydroxyl-protected coumarin derivatives 6a-e of 4-methyl3-(2,4-dihydroxyphenyl)-7-hydroxycoumarin (4) are key intermediates in the synthesis of unsymmetrical benzopyranobenzopyran compounds, a novel series of selective estrogen receptor modulators (SERMs). Free radical bromination of the 4-methyl group on 7-acetoxy-3-[(2,4-diacetoxy)phenyl]-4-methylcoumarin (6a) with NBS resulted in incomplete reactions and low to moderate yields (25-44%) of 4-bromomethyl product 7a. Lithiation of the 4-methyl group of coumarins 6b (R = SEM), 6c (R = MOM) and 6d (R = Bz) with LDA (1.1 - 1.7 equiv) or LHMDS (1.2-1.7 equiv) generated carbanion in THF at -76 degrees C, which was quenched with bromine (1.5-2.0 equiv) to afford 4-bromomethyl derivatives 7b-d in good yields (80-90%) in small scale reactions (2-20 g). The reaction yields declined to similar to 70% when the scale was increased to >= 80 g. Furthermore, treatment of 3-[(2,4-dimethoxy)phenyl]-7-methoxy-4-methylcoumarin (6e) with LHMDS (1.08 equiv) in THF followed by rapid inverse quenched with NBS (1.10 equiv) in THF at -76 degrees C, selectively produced the desired 4-bromomethyl compound 7e in excellent yield (> 90%) in both small (2-8 g) and large (80-150 g) scale reactions. A non-chromatographic process was developed to prepare 6e. This selective and efficient procedure was successfully transferred to the pilot plant to produce multikilograms of 4-bromomethyl coumarin 7e.