Department of Chemistry, Alzahra University, Vanak, Tehran, Iran.
Spectrochim Acta A Mol Biomol Spectrosc. 2010 Apr;75(4):1236-43. doi: 10.1016/j.saa.2009.12.033. Epub 2010 Jan 4.
Synthetic methods for several novel phosphoramidate compounds containing the P(O)NHC(O) bifunctional group were developed. These compounds with the general formula R(1)C(O)NHP(O)(N(R(2))(CH(2)C(6)H(5)))(2), where R(1)=CCl(2)H, p-ClC(6)H(4), p-BrC(6)H(4), o-FC(6)H(4) and R(2)=hydrogen, methyl, benzyl, were characterized by several spectroscopic methods and analytical techniques. The effects of phosphorus substituents on the rotation rate around the P-N(amine) bond were also investigated. (1)H NMR study of the synthesized compounds demonstrated that the presence of bulky groups attached to the phosphorus center and electron withdrawing groups in the amide moiety lead to large chemical-shift non-equivalence (Deltadelta(H)) of diastereotopic methylene protons. The crystal structures of CCl(2)HC(O)NHP(O)(NCH(3)(CH(2)C(6)H(5)))(2), p-ClC(6)H(4)C(O)NHP(O)(NCH(3)(CH(2)C(6)H(5)))(2), CCl(2)HC(O)NHP(O)(N(CH(2)C(6)H(5))(2))(2) and p-BrC(6)H(4)C(O)NHP(O)(N(CH(2)C(6)H(5))(2))(2) were determined by X-ray crystallography using single crystals. The coordination around the phosphorus center in these compounds is best described as distorted tetrahedral and the P(O) and C(O) groups are anti with respect to each other. In the compound Br-C(6)H(4)C(O)NHP(O)(N(CH(2)C(6)H(5))(2))(2) (with two independent molecules in the unit cell), two conformers are connected to each other via two different N-H...O hydrogen bonds forming a non-centrosymmetric dimer. In the crystalline lattice of other compounds, the molecules form centrosymmetric dimers via pairs of same N-H...O hydrogen bonds. The structure of CCl(2)HC(O)NHP(O)(N(CH(2)C(6)H(5))(2))(2) reveals an unusual intramolecular interaction between the oxygen of C=O group and amine nitrogen.
开发了几种含有 P(O)NHC(O) 双功能基的新型膦酰胺化合物的合成方法。这些通式为 R(1)C(O)NHP(O)(N(R(2))(CH(2)C(6)H(5)))(2) 的化合物中，R(1)=CCl(2)H、p-ClC(6)H(4)、p-BrC(6)H(4)、o-FC(6)H(4)，R(2)=氢、甲基、苄基，通过多种光谱方法和分析技术进行了表征。还研究了磷取代基对 P-N(胺)键旋转速率的影响。(1)H NMR 研究表明，磷中心连接的大基团和酰胺部分中的吸电子基团导致非对映体甲基亚甲基质子的化学位移不等（Deltadelta(H)）较大。通过单晶 X 射线衍射确定了 CCl(2)HC(O)NHP(O)(NCH(3)(CH(2)C(6)H(5)))(2)、p-ClC(6)H(4)C(O)NHP(O)(NCH(3)(CH(2)C(6)H(5)))(2)、CCl(2)HC(O)NHP(O)(N(CH(2)C(6)H(5))(2))(2)和 p-BrC(6)H(4)C(O)NHP(O)(N(CH(2)C(6)H(5))(2))(2)的晶体结构。这些化合物中磷中心周围的配位最好描述为扭曲的四面体形，并且 P(O)和 C(O)基团彼此呈反式。在化合物 Br-C(6)H(4)C(O)NHP(O)(N(CH(2)C(6)H(5))(2))(2)（晶胞中有两个独立的分子）中，两个构象体通过两个不同的 N-H…O 氢键相互连接，形成非中心对称二聚体。在其他化合物的晶体晶格中，分子通过相同的 N-H…O 氢键对形成中心对称二聚体。CCl(2)HC(O)NHP(O)(N(CH(2)C(6)H(5))(2))(2) 的结构揭示了 C=O 基团的氧和胺氮之间的一种不寻常的分子内相互作用。
