| 1403241-07-5

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 氧烷类
• CAS: 1403241-07-5
• 化学式: C₁₁H₁₈O₃
• 分子量: 208.177
• InChiKey: QMQGBJJCXLMPNY-URVFRIDLSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.31
• 重原子数：
  14.0
• 可旋转键数：
  4.0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.82
• 拓扑面积：
  38.69
• 氢给体数：
  1.0
• 氢受体数：
  3.0

反应信息

• 作为反应物：
  描述：

  在 4-甲基苯磺酸吡啶 、 sodium hydride 作用下， 以 四氢呋喃 、 乙醇 为溶剂， 生成 1-ethoxy-6-methoxy-([3,4-¹³C₂]hex-3-yne)-1,1,2,2,5,5,6,6-d₈
  参考文献：
  名称：

  Long-Lived Nuclear Singlet Order in Near-Equivalent ¹³C Spin Pairs

  摘要：

  Molecules that support C-13 singlet states with lifetimes of over 10 min in solution have been designed and synthesized. The C-13(2) spin pairs in the asymmetric alkyne derivatives are close to magnetic equivalence, so the C-13 long-lived singlet states are stable in high magnetic field and do not require maintenance by a radiofrequency spin-locking field. We suggest a model of singlet relaxation by fluctuating chemical shift anisotropy tensors combined with leakage associated with slightly broken magnetic equivalence. Theoretical estimates of singlet relaxation rates are compared with experimental values. Relaxation due to antisymmetric shielding tensor components is significant.

  DOI：

  10.1021/ja3089873
• 作为产物：
  描述：

  3,4-二氢-2H-吡喃 在 正丁基锂 、 4-甲基苯磺酸吡啶 、 potassium carbonate 作用下， 以 四氢呋喃 、 甲醇 、 二氯甲烷 为溶剂， 生成
  参考文献：
  名称：

  Long-Lived Nuclear Singlet Order in Near-Equivalent ¹³C Spin Pairs

  摘要：

  Molecules that support C-13 singlet states with lifetimes of over 10 min in solution have been designed and synthesized. The C-13(2) spin pairs in the asymmetric alkyne derivatives are close to magnetic equivalence, so the C-13 long-lived singlet states are stable in high magnetic field and do not require maintenance by a radiofrequency spin-locking field. We suggest a model of singlet relaxation by fluctuating chemical shift anisotropy tensors combined with leakage associated with slightly broken magnetic equivalence. Theoretical estimates of singlet relaxation rates are compared with experimental values. Relaxation due to antisymmetric shielding tensor components is significant.

  DOI：

  10.1021/ja3089873

文献信息

• Recycling and Imaging of Nuclear Singlet Hyperpolarization
  作者：Giuseppe Pileio、Sean Bowen、Christoffer Laustsen、Michael C. D. Tayler、Joseph T. Hill-Cousins、Lynda J. Brown、Richard C. D. Brown、Jan H. Ardenkjaer-Larsen、Malcolm H. Levitt

  DOI：10.1021/ja312333v

  日期：2013.4.3

  The strong enhancement of NMR signals achieved by hyperpolarization decays, at best, with a time constant of a few minutes. Here, we show that a combination of long-lived singlet states, molecular design, magnetic field cycling, and specific radiofrequency pulse sequences allows repeated observation of the same batch of polarized nuclei over a period of 30 min and more. We report a recycling protocol in which the enhanced nuclear polarization achieved by dissolution-DNP is observed with full intensity and then returned to singlet order. MRI experiments may be run on a portion of the available spin polarization, while the remaining is preserved and made available for a later use. An analogy is drawn with a "spin bank" or "resealable container" in which highly polarized spin order may be deposited and retrieved.