1. Purpose

One of the earliest and simplest C,H-correlation methods consists of only three rf.

pulses, and leads to a 2D spectrum where the C,H spin coupling remains visible in both dimensions; therefore it has been called FUCOUP (FUIly COUPled). The method does not distinguish between 'J(C,H) and long-range couplings; thus the full information is present in these spectra. Since the H,H spin coupling is also active, the method is very insensitive and gives complex spectra. For practical purposes in struc- tural elucidation it has therefore been replaced by more advanced methods (see Exps.

10.10–-10.17). To understand the basics of a C,H-correlation, however, this experiment provides an excellent start. In the educational experiment described here we demon- strate the phase-sensitive technique, with chloroform as an example.

2. Literature

[1] G. Bodenhausen, R. Freeman, J. Magn. Reson. 1977, 28, 471-476.

[2] R. L. Halterman, N. H. Nguyen, K. P. C. Vollhardt, J. Am. Chem. Soc. 1985, 107,

[3] G. E. Martin, A. S. Zektzer, Two-Dimensional NMR Methods for Establishing Molecular Connectivity, VCH, Weinheim, 1988, 171-174, 234.

[4] W. E. Hull, in: W. R. Croasmun, R. M. K. Carlson (eds.), Two-Dimensional NMR Spectroscopy, VCH, Weinheim, 1994, 2nd Edition, 382.

[5] W. Bauer, C. Griesinger, J. Am. Chem. Soc. 1993, 115, 10871-10882.

3. Pulse Scheme and Phase Cycle