Synthesis, Spectral and Single-Crystal Analyses of New Derivatives of 4-Amino-N-benzylpiperidine
作者:Ibrahim N. Hassan、Mou’ad A. Tarawneh、Bohari M. Yamin
DOI:10.14233/ajchem.2015.19174
日期:——
Two new compounds of thiourea derivatives of cinnamoyl and benzoylisothiocyanate with 4-amino-N-benzylpiperidine have been successfully synthesized. The new molecules, 1-(1-benzylpiperidine-4-yl)-3-benzoyl thiourea (I) (yield 83 %) and 1-(1-benzylpiperidine-4-yl)-3-(3-phenylacryloyl)thiourea (II) (yield 81%) were characterized by NMR, IR, UV, CHNS-O techniques as well as X-ray diffraction for single crystal. 1H NMR spectra show chemical shift at 10.77-10.80 ppm and 8.98-8.93 ppm were assigned for both dH(N) protons. Whereas, the chemical shift for 13C NMR analysis for C=O and C=S presence at dC 169-179 ppm. The significant stretching bands for n(N-H), n(C=S), n(C=O) and n(C-N) were around 3250, 800, 1650 and 1340 cm-1, respectively. The important chromophore of C=O was observed with a maximum absorption at around 300 nm in the UV spectra. The structures of (I) and (II) were determined via X-ray diffraction analysis for single crystal. Both molecules exhibit monoclinic crystal system and adopt trans-cis configuration with respect to the position of the phenyl and N-benzylpiperidine groups relative to the thione S atom, across their C-N bonds. There is one intramolecular N-H···O hydrogen bonds in both molecules that lead to the formation of pseudo-six-membered, in addition to a pseudo-five-membered ring, C9–H9···S1, in (I) which stabilizes the molecule. In the crystal lattice, the molecules are linked by intermolecular hydrogen bonds C–H···S and C–H···O forming chain network in (I) and polymeric in (II).
两种新化合物:4-氨基-N-苄基哌啶的肉桂酰和苯甲酰异硫氰酸酯的硫脲衍生物已成功合成。新分子1-(1-苄基哌啶-4-基)-3-苯甲酰硫脲(I)(产率83%)和1-(1-苄基哌啶-4-基)-3-(3-苯基丙烯酰)硫脲(II)(产率81%),通过NMR、IR、UV、CHNS-O技术以及单晶X射线衍射进行了表征。1H NMR光谱显示,dH(N)质子的化学位移在10.77-10.80 ppm和8.98-8.93 ppm之间。而13C NMR分析中C=O和C=S的化学位移为dC 169-179 ppm。n(N-H)、n(C=S)、n(C=O)和n(C-N)的显著伸缩带分别在3250、800、1650和1340 cm-1附近被观察到。C=O的重要色团在UV光谱中显示出约300 nm的最大吸收。通过单晶X射线衍射分析确定(I)和(II)的结构。两种分子均展现单斜晶系,并在苯基和N-苄基哌啶基团相对于硫烯S原子的位点上采用顺-反构型。两个分子中都有一个分子内N-H···O氢键,导致伪六元环的形成,此外(I)中还有一个伪五元环C9–H9···S1,从而稳定了分子。在晶格中,这些分子通过分子间氢键C–H···S和C–H···O相互连接,形成(I)中的链状网络和(II)中的聚合物结构。