The Structure of 1H-Perimidin-2(3H)-one and Its Derivatives in the solid state (x-ray crystallography and CP/MAS13C-NMR), in solution (13C-NMR), and in the gas phase (mass spectrometry)
作者:Rosa M. Claramunt、Julio Dotor、Dionisia Sanz、Concepci�n Foces-Foces、Antonio L. Llamas-Saniz、Jos� Elguero、Robert Flammang、Jean Pierre Morizur、Erik Chapon、Jeanine Tortajada
DOI:10.1002/hlca.19940770115
日期:1994.2.9
The X-ray crystal and molecular structures of 1-methyl- 1H-perimidin-2(3H)-one (5b) and 1,3-dimethyl-1H-perimidin-2(3H)-one (6) were determined. The crystals are built of piles of dimers faced head-to-head in 5b and of alternating independent head-to-tail molecules in 6, both along the b axis. Semiempirical calculations at the AM 1 level revealed that the eclipsed conformation of the Me groups with
1-甲基-1 H -perimidin-2(3 H)-one(5b)和1,3-二甲基-1 H -perimidin-2(3 H)-one(6)的X射线晶体和分子结构被确定。将晶体内置面对头-头在二聚体的桩5B和交替独立头-尾分子6,二者沿b轴。在AM 1水平的半经验计算表明,在晶体中发现的Me基相对于CO基的蚀变构象是最稳定的。整个分子缺乏平面性是堆积力的结果,因为在计算中未发现。在溶液(1 H和13 C)和固态(CP / MAS 13 C)下,对1 H -perimidin-2(3 H)-one(2)和1 H-苯并咪唑-进行了比较NMR研究。2(3 H)-一(3)的结论是,在两个杂环中,羰基互变异构体含量最高。气相的结构通过质谱法得到。在的情况下3,电离后互变异构体失去CO的氧代基,而的氧代形式2个tautomerizes成羟基形式失去,H 2 ö之后的[1,3] -H移。AM 1的计算是在地面上进行,电离态的2。