For overlaped signals, you can use some experiments to solve this problem. One is the use of the technique CSSF where signals overlap with at least 2 Hz separation between them using selective excitation (ref.:P.T. Robinson et al., In phase selective excitation of overlapping multiplets by gradient-enhanced chemical shift selective filters. Journal of Magnetic Resonance 170 (2004) 97–103)97–103 link text). The other is the use of SELINCOR technique (1D version of HMQC experiment). Irradiatin the olefinic carbon, you will obtain the 1H spectrum via 1J CH correlation. (REF.: S. Berger., Journal of Magnetic Ressonance 81 (1989), 561-564 link text)
