1-benzofuran-2-yl-2-dibenzylamino-ethanone | 751465-03-9

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 苯并呋喃
• 英文名称: 1-benzofuran-2-yl-2-dibenzylamino-ethanone
• 英文别名: 1-Benzofuran-2-yl-2-dibenzylamino-aethanon
• CAS: 751465-03-9
• 化学式: C₂₄H₂₁NO₂
• 分子量: 355.436
• InChiKey: KXKINPJOMNMFCC-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.95
• 重原子数：
  27.0
• 可旋转键数：
  7.0
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.125
• 拓扑面积：
  33.45
• 氢给体数：
  0.0
• 氢受体数：
  2.0

反应信息

• 作为反应物：
  描述：

  1-benzofuran-2-yl-2-dibenzylamino-ethanone 在 palladium dihydroxide 盐酸 、 氢气 、 N,N-二异丙基乙胺 作用下， 以 四氢呋喃 、 甲醇 、 乙酸乙酯 为溶剂， 5.0~23.0 ℃ 、413.69 kPa 条件下， 反应 16.75h， 生成 1-(1-Benzofuran-2-yl)-2-[[2-(1-benzofuran-2-yl)-2-hydroxyethyl]-benzylamino]ethanone
  参考文献：
  名称：

  Stereocontrol between Remote Atom Centers in Acyclic Substrates. Anti Addition of Hydride to 1,5-, 1,6-, and 1,7-Hydroxy Ketones

  摘要：

  For conformationally unconstrained, acyclic organic compounds, the control of stereogenic centers at remote positions of a chain, that is, at a distance of four or more atom centers, remains a challenging problem in asymmetric synthesis. We report on our studies of 1,5, 1,6, and 1,7 diastereoselectivity in hydride reductions of acyclic hydroxy amino ketones and related compounds, which were sparked by our discovery of high 1,5 diastereocontrol (>10:1) with substrates such as 17 and 23. We have been able to achieve both high 1,5- and 1,6-anti diastereocontrol in the reduction of 1,5- and 1,6-hydroxy ketone substrates, respectively. However, the level of 1,7-anti diastereocontrol with 1,7-hydroxy ketones was only moderate. More specifically, reduction of 23 to 24 with R-alpine-hydride or Zn(BH4)(2) in CH2Cl2 (predominantly) at -78 degrees C gave high 1,5-anti stereoselectivity (anti/syn = 10:1 or 13:1, respectively), and reduction of 34 to 35 with R-alpine-hydride (CH2Cl2) gave high 1,6-anti selectivity (anti/syn = 12:1, respectively), whereas reduction of 46 to 44 with R-alpine-hydride (CH2Cl2) gave only moderate 1,7-anti stereoselectivity (anti/syn = 3:1). Results for reductions of 1,5- and 1,6-hydroxy ketone substrates having the N-benzyl structural subunit replaced (i.e., 27 --> 28, 29 --> 30, 31 --> 32, 52 --> 53, 54a --> 55a, 54b --> 55b, 54c --> 55c, and 56 --> 57) clearly indicate that the stereoelectronic character of this subunit plays a critical. role in the attainment of high anti asymmetric induction. Thus, while we obtained exceptionally high 1,6-anti stereoselectivity in the reduction of the N-mesitylmethyl substrate, 54c, to 1,6-diols 55c (anti/syn = 22:1) with R-alpine-hydride at -78 degrees C in CH2Cl2, the N-methyl substrate, 54b, gave a relatively modest anti/syn ratio of 3:1. The diminished anti/syn ratio of 4:1 in the R-alpine-hydride reduction of methoxy amino ketone 50 to 51 also indicates the importance of the free hydroxyl group for attaining high 1,6-anti stereoselectivity. To rationalize the high remote anti stereocontrol in such acyclic systems, we discuss a chelation-controlled mechanism, involving external hydride addition to a bicyclic metal complex with a coordinated ketone carbonyl (e.g., 33) vs internal hydride addition to a monocyclic metal complex with an uncoordinated ketone carbonyl (e.g., 58).

  DOI：

  10.1021/jo981341m
• 作为产物：
  描述：

  2-乙酰基苯并呋喃 在 2-吡咯烷酮 、 pyrrolidone hydrotribromide 作用下， 反应 3.0h， 生成 1-benzofuran-2-yl-2-dibenzylamino-ethanone
  参考文献：
  名称：

  Stereocontrol between Remote Atom Centers in Acyclic Substrates. Anti Addition of Hydride to 1,5-, 1,6-, and 1,7-Hydroxy Ketones

  摘要：

  For conformationally unconstrained, acyclic organic compounds, the control of stereogenic centers at remote positions of a chain, that is, at a distance of four or more atom centers, remains a challenging problem in asymmetric synthesis. We report on our studies of 1,5, 1,6, and 1,7 diastereoselectivity in hydride reductions of acyclic hydroxy amino ketones and related compounds, which were sparked by our discovery of high 1,5 diastereocontrol (>10:1) with substrates such as 17 and 23. We have been able to achieve both high 1,5- and 1,6-anti diastereocontrol in the reduction of 1,5- and 1,6-hydroxy ketone substrates, respectively. However, the level of 1,7-anti diastereocontrol with 1,7-hydroxy ketones was only moderate. More specifically, reduction of 23 to 24 with R-alpine-hydride or Zn(BH4)(2) in CH2Cl2 (predominantly) at -78 degrees C gave high 1,5-anti stereoselectivity (anti/syn = 10:1 or 13:1, respectively), and reduction of 34 to 35 with R-alpine-hydride (CH2Cl2) gave high 1,6-anti selectivity (anti/syn = 12:1, respectively), whereas reduction of 46 to 44 with R-alpine-hydride (CH2Cl2) gave only moderate 1,7-anti stereoselectivity (anti/syn = 3:1). Results for reductions of 1,5- and 1,6-hydroxy ketone substrates having the N-benzyl structural subunit replaced (i.e., 27 --> 28, 29 --> 30, 31 --> 32, 52 --> 53, 54a --> 55a, 54b --> 55b, 54c --> 55c, and 56 --> 57) clearly indicate that the stereoelectronic character of this subunit plays a critical. role in the attainment of high anti asymmetric induction. Thus, while we obtained exceptionally high 1,6-anti stereoselectivity in the reduction of the N-mesitylmethyl substrate, 54c, to 1,6-diols 55c (anti/syn = 22:1) with R-alpine-hydride at -78 degrees C in CH2Cl2, the N-methyl substrate, 54b, gave a relatively modest anti/syn ratio of 3:1. The diminished anti/syn ratio of 4:1 in the R-alpine-hydride reduction of methoxy amino ketone 50 to 51 also indicates the importance of the free hydroxyl group for attaining high 1,6-anti stereoselectivity. To rationalize the high remote anti stereocontrol in such acyclic systems, we discuss a chelation-controlled mechanism, involving external hydride addition to a bicyclic metal complex with a coordinated ketone carbonyl (e.g., 33) vs internal hydride addition to a monocyclic metal complex with an uncoordinated ketone carbonyl (e.g., 58).

  DOI：

  10.1021/jo981341m

文献信息

• Amino Alcohol Studies. 2,3-Dihydrobenzofuran Derivatives
  作者：Alfred Burger、Adolph J. Deinet

  DOI：10.1021/ja01220a022

  日期：1945.4