作者:Alan R. Katritzky、Bradley L. Duell、John K. Gallos、H. Dupont Durst
DOI:10.1002/mrc.1260271102
日期:1989.11
The 13C NMR spectra for selected 2-iodosobenzoic acids, their sodium salts and the sodium salts of the corresponding iodoxybenzoic acids were measured and carbon assignments made using 2D and NOE experiments and relaxation times. Iodoso and iodoxy groups deshielded the ipso-carbon in these compounds by approximately 25 and 55 ppm, respectively, relative to the corresponding iodo compounds. The 13C NMR spectra of the 2-iodosobenzoate anions were almost identical with those of the corresponding free acids, both possessing cyclic structures. The iodoxybenzoic acids are either insoluble in, or oxidize, suitable NMR solvents (i.e. DMSO-d6, DMF-d7). The cyclic structure postulated for iodoxybenzoate anions is supported by their 13C chemical shifts.
对选定的2-碘索苯甲酸及其钠盐以及相应的氧碘苯甲酸钠盐进行了13C NMR光谱测定,并利用二维和NOE实验及弛豫时间进行了碳位的分配。在这些化合物中,碘素和氧碘基团使ipso碳的屏蔽降低了大约25和55 ppm,相对于相应的碘化物。2-碘索苯甲酸盐阴离子的13C NMR光谱与相应的自由酸几乎相同,两者均具有环状结构。氧碘苯甲酸在适当的NMR溶剂(即DMSO-d6、DMF-d7)中要么不溶解,要么会被氧化。对氧碘苯甲酸盐阴离子所假定的环状结构得到了它们的13C化学位移的支持。