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在核磁共振实验中,~(13)C 的质子宽带去偶和偏共振谱已被广泛地用来测定有机化合物的结构。由质子宽带去偶谱可以获知被测物的碳数目及碳的类别,如有无烯碳、芳碳、羰基碳及烷基碳等。(?)C 的偏共振谱可用来识别伯仲、叔、季碳,以助于图谱解析。但核磁共振在实际测试中,特别是在被测化合物含碳数较多、分子结构较复杂的情况下,偏共振谱中许多裂分峰相互重迭而无法识别,因此要使碳的每条谱线得到正确归属颇为困难。近几年来,W·Brown 和 J·N·Shoolery 等人采用自旋回波(spin-echo)脉冲技术将甲基、
In the NMR experiments, the broadband proton broadband decoupling and partial resonance spectra of ~ (13) C have been widely used to determine the structure of organic compounds. By the proton broadband to the spectrum can be informed of the carbon number of the measured object and the type of carbon, such as the absence of olefin carbon, aromatic carbon, carbonyl carbon and alkyl carbon. (?) C partial resonance spectrum can be used to identify primary, tertiary, quaternary carbon, to help the map analysis. But in the actual test of NMR, especially in the case of more carbon number and complex molecular structure of the tested compound, many crack peaks in the partial resonance spectrum overlap each other and can not be identified. Therefore, The correct assignment of spectral lines is difficult. In recent years, W. Brown and JN Shoolery et al. Used a spin-echo pulse technique to convert methyl,