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五氟丙酰基苯甲酰基亚甲基三苯基膦的亚甲基上带有两个强的吸电子基团,属单斜晶系,空间群C2/C,晶胞参数α=11.271(3),b=18.253(6),c=23.938(7)A;β=91.09(2)°;Z=8.用四圆衍射仪收集X射线衍射强度数据,用直接法解晶体结构,用块对角矩阵最小二乘法进行结构修正,参与修正的可观测独立反射点共3146个.最终R=0.075.本文对该膦叶立德的结构进行了测定和讨论,并与已报道的相应的胂叶立德进行比较.叶立德碳原子C(1)与相应的胂叶立德相同,以sp~2杂化轨函参与σ键.P—C(1)键长1.748(5)A,键级1.60;而相应的胂叶立德中As—C(1)的键级1.46,表明前者的“ylene”型结构的贡献比后者大,导致前者的化学活性小于后者.在各种“ylide”型结构中,两者均以负电荷离域化的结构3贡献较大.
Pentafluoropropionylbenzoylmethylene triphenylphosphine methylene with two strong electron-withdrawing group, is a monoclinic, space group C2 / C, unit cell parameters α = 11.271 (3 ), b = 18.253 (6), c = 23.938 (7) A, β = 91.09 (2) °, and Z = 8. The X-ray diffraction intensity data were collected using a four-circular diffractometer and the crystal structure was solved directly The structure of the diagonal matrix least squares method was modified and the number of observable independent reflection points involved in the correction was 3146. Finally, R = 0.075.The structure of this phosphonium ylide was measured and discussed in this paper, and the corresponding reported arsonium ylide (1) is the same as the corresponding arsonium ylide, and the sp ~ 2 hybridization orbital participates in the σ bond.The bond length of P-C (1) is 1.748 (5) A and the linkage order is 1.60, while the corresponding arsine The bond level of As-C (1) in Yilitide is 1.46, indicating that the former has a larger contribution to the “ylene” type structure than the latter, resulting in a lower chemical activity of the former. In each of the “ylide” Structure 3, delocalized with a negative charge, contributes more.