1H Indirect Detected 13C Low-Abundance Single-Transition Correlation Spectroscopy (HICLASS)-13C Homonuclear Correlation at Natural Abundance

A novel proton-detected C-13 homonuclear correlation experiment is reported at natural abundance, viz., H-1 Indirect detected C-13 Low-Abundance Single-transition correlation Spectroscopy (HICLASS). HICLASS is based on the evolution of C-13 single-quantum single transitions, followed by their mixing, and H-1 detection subsequent to heteronuclear transfer. Reduced relaxation losses during the evolution time and partial selectivity in the H-1 multiplet structure result in enhanced sensitivity of HICLASS. The superior performance of HICLASS is demonstrated for H-1-detected C-13 correlation work.