House K L, O'Connor M J, Silks L A, Dunlap R B, Odom J D
Department of Chemistry and Biochemistry, University of South Carolina, Columbia 29208.
Chirality. 1994;6(3):196-201. doi: 10.1002/chir.530060306.
Previously, a diazaphospholidine has been synthesized and evaluated as a chiral derivatizing reagent for the determination of the optical purity of chiral alcohols via 31P NMR spectroscopy (Alexakis et al., J. Org. Chem. 57:1224-1237, 1992). Our laboratory is interested in the advantageous and practical applications of 77Se NMR spectroscopic studies in many facets of chemistry and biochemistry. To this end we have used this diazaphospholidine as a starting point and have investigated chiral alcohols coupled to an optically pure diazaselenophospholidine. The diastereomers formed were then evaluated by 77Se NMR spectroscopy, and these results were compared to the 31P NMR results published by Alexakis and co-workers. It was found that addition of the Se atom produced diastereomers that were air stable and, in many cases, the individual diastereomers could be distinguished by 77Se NMR spectroscopy. Preliminary results indicate that the 77Se nucleus is somewhat more sensitive to remotely disposed chiral centers than is the 31P nucleus. Furthermore, because of their stability, these compounds do not readily decompose and can, therefore, be studied by a variety of chromatographic and spectroscopic techniques.
此前，已合成了一种二氮杂磷环戊烷，并将其作为手性衍生化试剂，用于通过31P核磁共振光谱法测定手性醇的光学纯度（亚历克西斯等人，《有机化学杂志》57:1224 - 1237，1992年）。我们实验室对77Se核磁共振光谱研究在化学和生物化学诸多方面的优势及实际应用感兴趣。为此，我们以这种二氮杂磷环戊烷为起点，研究了与光学纯二氮杂硒磷环戊烷偶联的手性醇。然后通过77Se核磁共振光谱法评估形成的非对映异构体，并将这些结果与亚历克西斯及其同事发表的31P核磁共振结果进行比较。发现硒原子的加入产生了对空气稳定的非对映异构体，并且在许多情况下，各个非对映异构体可以通过77Se核磁共振光谱法区分。初步结果表明，77Se核对于远程手性中心的敏感度比31P核略高。此外，由于这些化合物的稳定性，它们不易分解，因此可以通过多种色谱和光谱技术进行研究。
