Ghosh Soumen, Mukhopadhyay Rupa, Helliwell Madeleine, Mukherjee Alok K
Department of Physics, Jadavpur University, Kolkata 700 032, India.
Acta Crystallogr C. 2007 Aug;63(Pt 8):o496-500. doi: 10.1107/S0108270107032234. Epub 2007 Jul 26.
The pyrazine ring in two N-substituted quinoxaline derivatives, namely (E)-2-(2-methoxybenzylidene)-1,4-di-p-tosyl-1,2,3,4-tetrahydroquinoxaline, C(30)H(28)N(2)S(2)O(5), (II), and (E)-methyl 2-[(1,4-di-p-tosyl-1,2,3,4-tetrahydroquinoxalin-2-ylidene)methyl]benzoate, C(31)H(28)N(2)S(2)O(6), (III), assumes a half-chair conformation and is shielded by the terminal tosyl groups. In the molecular packing of the compounds, intermolecular C-H...O hydrogen bonds between centrosymmetrically related molecules generate dimeric rings, viz. R(2)(2)(22) in (II) and R(2)(2)(26) in (III), which are further connected through C-H...pi(arene) hydrogen bonds and pi-pi stacking interactions into novel supramolecular frameworks.
两种N-取代喹喔啉衍生物中的吡嗪环，即(E)-2-(2-甲氧基亚苄基)-1,4-二对甲苯磺酰基-1,2,3,4-四氢喹喔啉，C(30)H(28)N(2)S(2)O(5)，(II)，以及(E)-2-[(1,4-二对甲苯磺酰基-1,2,3,4-四氢喹喔啉-2-基亚甲基]苯甲酸甲酯，C(31)H(28)N(2)S(2)O(6)，(III)，呈半椅式构象，并被末端对甲苯磺酰基所屏蔽。在这些化合物的分子堆积中，中心对称相关分子之间的分子间C-H...O氢键形成二聚环，即(II)中的R(2)(2)(22)和(III)中的R(2)(2)(26)，它们通过C-H...π(芳烃)氢键和π-π堆积相互作用进一步连接成新颖的超分子框架。
