HMBC–RELAY: a combined technique for the differentiation of simultaneously detected 2J(C,H) and nJ(C,H) connectivities

✍ Scribed by Thomas Sprang; Peter Bigler

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 404 KB
• Volume: 42
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1311

✦ Synopsis

Abstract

We present a new pulse sequence that detects simultaneously ^n^J(C,H) and ^2^J(C,H) connectivities. The corresponding coherences are created along independent pathways and therefore can be separated into two different subspectra. One spectrum is to show all ^n^J(C,H) connectivities and the other is to show exclusively ^2^J(C,H) connectivities. In contrast to the previously published ^2^J/^n^J experiment, this sequence detects the ^2^J(C,H) connectivities via a C,H,H‐RELAY pathway leading to an intensification of the ^2^J(C,H) signals. Strictly, the ^2^J(C,H) spectrum does not show ^2^J(C,H) but ^3^J(H,H) coupling interactions within ^13^CH~k~–^12^CH~l~ fragments. Therefore, ^2^J(C,H) signals can appear even if the corresponding ^2^J(C,H) coupling constant is zero. Copyright © 2003 John Wiley & Sons, Ltd.