摘要
研究并合成了席夫碱（Ｉ）（Ｃ３０Ｈ２８Ｎ３Ｏ４）和（Ⅱ）（Ｃ３８Ｈ３２Ｎ２Ｏ４），通过单晶Ｘ射线衍射测定了它们的晶体结构．（Ⅰ）为单斜晶系，空间群为得出晶胞有关参数；（Ⅱ）为单斜晶系，空间群为，得出晶胞有关参数．晶体结构采用直接法解出，用块矩阵最小二乘法修正，单位权重，最后的一致性因子为：（Ⅰ）Ｒ＝０．０４７；（Ⅱ）Ｒ＝０．０７６．两个席夫碱均为反式结构，分子均有对称中心，并座落在晶体的对称中心上．
Schiff base (I) (C30H28N2O4) and (II) (C38H32N2O4) have been synthesized. Their crystal strutures have been determined making use of single crystal X-ray diffraction Schiff base (I) is seen to be a monoclinic crystal with the space group P21/c. Its cell dimensions are a=0.512 3(1) nm, b= 1.147 9(4) nm, c=2.095 1(6) nm, β=95.42(2)°, V=1.2265(6)nm3, Z=2. Schiff base (II) is also monoclinic with the space group C2/c,and having a=2.472 2(7) nm, b =0.994 8 (3)nm, c= 2.058 1 (6) nm, β= 143.99(1)°, V=2.976(1) nm3, Z=4. The Crystal structure has been solved by the direct method, refined by the method of block-matrix least squares and unit weighted. The final residuals are found as R=0.047 (I) and R=0.076 (II ). Their structures are trans. The molecules have a centre of symmetry and are situated on the centres of symmetry of the crystals.
出处
《北京理工大学学报》
EI
CAS
CSCD
1996年第2期194-198,共5页
Transactions of Beijing Institute of Technology
关键词
席夫碱
晶体结构
对称中心
合成
Schiff base
crystal structures
centre of symmetry
trans
