Design and characterization of a calixarene inclusion compound for calibration of long-range carbon–fluorine distance measurements by solid-state NMR

详细信息    查看全文

• 作者：Daniel J. Fowler ; Peter G. Khalifah ; Lynmarie K. Thompson
• 关键词：Carbon– ; fluorine distance measurements ; REDOR ; Rotational echo double resonance ; Magic angle spinning ; Calixarene
• 刊名：Journal of Magnetic Resonance
• 出版年：2010
• 出版时间：November 2010
• 年：2010
• 卷：207
• 期：1
• 页码：153-157
• 全文大小：634 K

文摘

An inexpensive, easily synthesized calixarene:fluorotoluene host:guest inclusion complex has been designed for optimization and calibration of solid-state NMR measurements of carbon–fluorine distances using Rotational Echo DOuble Resonance (REDOR). Complexation of the fluorotoluene with the calixarene host separates the molecules such that simple two-spin behavior is observed for one site with a 4.08 Å carbon–fluorine distance. Fluorotoluene dynamics within the calixarene matrix cause motional averaging of the dipolar couplings, which makes it possible to easily optimize REDOR experiments and test their accuracy for relatively long distance measurements (>6.6 Å). This provides a new tool for accurate REDOR measurements of long carbon–fluorine distances, which have important applications in the characterization of fluorine-containing drugs, proteins, and polymers.