- 作者: 劉陵崗 ; 施雲娥 ; 李艷鄉
- 作者服務機構: 中央研究院化學研究所
- 中文摘要: Single crystal x-ray structures of the diastereomeric 2-dimethylamino-4-phenyl-2H-1,3,2-oxazaphosphorinane-2-oxides, 5c and 6c, have been determined. The pair has been prepared in a straightforward manner by reaction of 3-amino-3-phenylpropanol with Me/sub 2/NP(O)Cl/sub 2/, and separated into pure forms by column chromatography. Crystal data of 5c: space group P2/sub 1/n,a=11,087(3), b=6,087(6), c=18,465(6).ANG.,.beta.=98.40(3).degree., R=0.035 for 1845 reflections. Crystal data of 6c: space group P2/sub 1/n,a=11,176(2), b=6.893(2), c=16.673(3).ANG., .beta.=95.29(1).degree., R=0.037 for 1253 reflections. The fast-migrating 5c is cis (Ph and P=O group cis) with the configuration of 2RS, 4SR. The slow migrating 6c is trans with the configuration of 2RS, 4RS. In both structures the 1,3,2-oxazaphosphorinane rings are chair like with the P-end essentially flattened. The skeleton made up with 4-phenyl-1,3,2-oxazaphosphorinane is essentially the same. With a conformationally demanding 4-phenyl substituent, 5c has an axial Me/sub 2/N whereas 6c has an equatorial Me/sub 2/N. For 6c, the exocyclic P-N bond has a partial double bond character: the geometry about exocyclic N is planar. On the other hand, for 5c, the geometry about exocyclic N deviates considerably from planarity, the sum of the angles around N being 348.1.degree. In the crystalline state, the screw-related 5c molecules are hydrogen bonded whereas in the crystalline state, the centro-symmetrically related 6c molecules are paired-up by hydrogen bonds, both through the N-H and P=O system.
- 英文摘要: --
- 中文關鍵字: X-Ray Structure Analysis, 1,3,2-Oxazaphosphorinane Ring System
- 英文關鍵字: X射線結構分析