【作者】 齐林；

【导师】 赵玉芬； 曹书霞；

【作者基本信息】 郑州大学 ， 有机化学， 2013， 硕士

【摘要】 在生物化学中,五配位磷化合物作为中间体或过渡态被广泛的提出。氢膦烷是一类特殊的五配位磷化合物,由于该化合物具有P-H键,能发生很多类型的化学反应。到目前为止,尽管对氢膦烷的相关化学反应活性有了一定的认识,但是对于含有氨基酸结构单元的氨基酸氢膦烷的化学反应研究较少。本课题组已经合成了多种双氨基酸螺环氢膦烷,并对这些化合物与胺、酚的类Atherton-Todd反应进行了深入的研究,在此基础上,本文主要以双缬氨酸氢膦烷(△构型)与双苯丙氨酸氢膦烷(∧构型)作为研究对象,系统地研究了由双氨基酸氢膦烷合成焦螺磷烷酯的反应及其立体化学特点,提出了反应机理。探究了五配位磷化合物的波谱性质与立体构型之间的关系。主要研究双缬氨酸氢膦烷(△构型)和双苯丙氨酸氢膦烷(∧构型)合成焦螺磷烷酯的反应,从试剂,温度,缚酸剂,卤化剂,催化剂五方面优化了反应条件,在最佳反应条件下扩充了双分子氨基酸氢膦烷的种类,合成了系列新型五配位焦螺磷烷酯化合物,这些化合物均通过核磁共振波谱(NMR)、电喷雾质谱(ESI-MS)等分析手段进行了结构表征。对其反应机理的研究发现,从原料到P-C1中间体,磷原子构型保持。由中间体到焦螺磷烷酯,由于氨基酸烷基取代基位阻的差异和磷原子构型的不同,亲核试剂选择优先从位阻较小的一侧进攻,因此不同的起始双氨基酸氢膦烷得到了不同的反应结果。对于磷原子背后立体位阻较小的双缬氨酸氢膦烷(△构型)只生成一种焦螺磷烷酯,而对于背后位阻较大的双苯丙氨酸氢膦烷(A构型)则生成了两种焦螺磷烷酯,为一对以磷为手性中心的非对映异构体。本课题组在研究双氨基酸氢膦烷与胺、酚的类Atherton-Todd反应的立体化学特征的过程中,得到了系列新型的五配位磷烷化合物,但由于有些化合物的单晶很难得到,无法确定磷原子的绝对构型,因此不能够清楚的阐述反应的立体构型变化规律。所以本文通过研究绝对构型已知的五配位磷化合物的波谱性质,探究了磷原子的立体绝对构型与五配位磷化合物的波谱性质之间的关系,尝试依据波谱性质来判断五配位磷化合物的构型,该项工作对进一步研究氢膦烷有关反应的立体化学机理具有重要意义。更多还原

【Abstract】 Pentacoordinate phosphorus compounds as intermedinates or transition state species are proposed in numerous bioblogical processes. As a special type of pentacoordinate phosphorus compounds involving P-H bond. Hydrospirophosphorane is active enough to be precursors for organic synthesis. Until now, there were some reports about hydrophosphoranes, however, there was few research on hydrospirophosphoranes involving bi-amino acid unit. After the numerous bi-amino acid hydrospirophosphoranes were synthesized in our group, we studied in depth the Atherton-Todd reaction of bi-amino acid hydrospirophosphoranes with amine and phenol. In this paper, the chemical activity and the configuration of bi-valine Hydrospirophosphorane and bi-phenylalanine Hydrospirophosphorane to synthesize pyrospirophosphoranes were studied, and a probable mechanism was proposed in terms of experiments observations. Furemore, the relationship between the phosphorus configuration and the NMR spectrum data was explored and summarized.The synthesis of pyrospirophosphoranes from bi-valine Hydrospirophosphorane-A and bi-phenylalanine Hydrospirophosphorane-A were investigated. First, the effects of solvent, temperature, alkalis, halogenating agent and catalyst on the reaction were studied. Then in optimum conditions numerous new pyrospirophosphoranes were obtained in good yields. The structures of these new compounds were characterized by ESI-MS、 NMR and IR spectra. To explore the mechanism of the reaction, the single crystal of the intermediate was gained. The single crystal data suggested that the configuration of phosphorus chiral center of the intermediates was stereoretention. However, the configuration of the products depended upon the steric hindrance of substituent group and phosphorus configuration of bi-amino acid hydrospirophosphoranes. Only one configuration of pyrospirophosphorane from bi-valine Hydrospirophosphorane-A with smaller steric hindrance was obtained, while two diastereoisomers of pyrospirophosphoranes were produced, from bi-phenylalanine Hydrospirophosphorane-Awith bigger steric hindrance.In the process of research about the configuration of Atherton-Todd reaction between bi-amino acid hydrospirophosphorane with amine and phenol, since we were not able to determine the absolute configurations of phosphorus atoms, it is difficult to analyze clearly the change rule of configuration in the reaction. In this paper, we explored the relationship of the phosphorus configuration and spectrum character of pentacoordinate phosphorus compounds in the base of phosphorane whose absolute configuration could be confirmed by single crystal data. As a result, according to the spectrum character of some pentacoordinate phosphorus compounds, their absolute configurations might be determined.更多还原