微波辐射下氯代苯胺基吡咯亚胺类化合物的合成及其晶体结构

Synthesis of Chloroaniline Based Mono(imino) pyrroles Under Microwave Irradiation and Its Crystal Structure

将2-乙酰基吡咯作为前驱体与取代位置不同的芳香胺:邻氯苯胺、间氯苯胺、对氯苯胺在微波辐射下反应时发现,当氯原子(钝化基团)处于苯环的间位及对位时,芳香胺与2-乙酰基吡咯可成功发生希夫碱缩合反应得到吡咯亚胺化合物Ⅰa和Ⅰb;而当氯原子处于苯环邻位时,二者不发生反应。Ⅰa和Ⅰb的结构经X射线单晶衍射,1HNMR、IR、MS和元素分析表征证实为预期化合物。X射线单晶衍射测定结果表明,Ⅰa属单斜晶系,空间群C2/C,晶体参数a=2.372 2(15)×10-9m,b=5.720(4)×10-10m,c=1.686 8(11)×10-9m,β=98.404(10)°,V=2.264(3)×10-27m3,Z=8,D c=1.283 g/cm3,R1=0.041 9,ωR2=0.119 5。Ⅰb属单斜晶系,空间群P21/C,晶胞参数a=1.332 3(3)×10-9m,b=9.802(2)×10-10m,c=9.107(2)×10-10m,β=109.212(4)°,V=1.123 1(4)×10-27m3,Z=4,D c=1.293 g/cm3,R1=0.047 2,ωR2=0.118 9。对芳香胺上钝化基团的位置对希夫碱缩合反应的影响也进行了初步探讨。

Using 2-acetylpyrrole and a couple of aromatic amines, such as 3-chloroaniline and 4- chloroaniline, as the raw materials, two chloroaniline based mono （imino）pyrroles 2-{t 1-[ （3- chlorophenyl） imino ] ethyl} pyrrole （ I a ） and 2- { 1- [ （ 4-chlorophenyl ） imino ] ethyl} pyrrole （ I b ） were prepared under microwave irradiation. No indication showed the reaction having taken place between 2-acetylpyrrole and 2-chloroaniline. These structures were characterized by means of X-ray single crystal diffraction, ^1HNMR, IR, MS and elemental analysis. I a belongs to monoclinic system, of the space group C2/C with a = 2. 372 2 （ 15 ） × 10 ^-9 m, b = 5. 720 （4） × 10^ - 10 m, c = 1. 686 8 （ 11 ） ×10 ^-9 m ,β= 98.404（10） °, V = 2. 264 （3） × 10 ^-27 m^3 ,Z = 8 ,Dc = 1. 283 g/cm^3 ,R1 = 0. 041 9 ,ωR2 =O. 119 5. I b also belongs to monoclinic system,of the space group P2t/C with α = 1. 332 3（3） × 10^-9m,b =9. 802（2） × 10^-10 m,c =9. 107（2）× 10^-10 m,β = 109. 212（4）°, V = 1. 123 1 （4） × 10^-27m^3 ,Z = 4, Dc = 1. 293 g/cm^3 , R1 = 0. 047 2, ωR2 = 0. 118 9. The reaction mechanism between the position of deactivation group on the aromatic amines and the Schiff base condensation was also discussed.