Superlative Scaffold of 1,2,4-Triazole Derivative of Glycine Steering Linear Chain to a Chiral Helicate

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• 作者：Marinela M. Dirtu ; Christine Neuhausen ; Anil D. Naik ; Alexandre Le虂onard ; Francois Robert ; Jacqueline Marchand-Brynaert ; Bao-Lian Su ; Yann Garcia
• 刊名：Crystal Growth & Design
• 出版年：2011
• 出版时间：April 6, 2011
• 年：2011
• 卷：11
• 期：4
• 页码：1375-1384
• 全文大小：1109K
• 年卷期：v.11,no.4(April 6, 2011)
• ISSN：1528-7505

文摘

Solvothermal and classical synthesis with an identical recipe involving 4H-1,2,4-triazol-4-yl acetic acid (HL1) and CdCl₂ afforded two-dimensional (2D) (1) and one-dimensional (2) coordination polymers, respectively. Hexagonal plate-like crystals of [Cd₂(L1)₂Cl₂] (1), which crystallize in the chiral orthorhombic space group (P2₁2₁2₁), were obtained in high yield. The 1,2,4-triazole-4-yl acetate (L1) ligand, which has a significant kink in the spacer, leads to the formation of a Cd^II complex displaying a 2D single-stranded helical array. The pitch height of the helix is equal to the length of the crystallographic a axis (7.579 脜) which comprises two cadmium atoms and two ligands. Solid-state emission of 1 shows a strong emission band around 465 nm with photoexcitation at 290 nm. Mercury porosimetry measurements reveal pore size distribution with a diameter of 80, 10, and 1 渭m. BET shows no preference for N_2(g) but a low H_2(g) adsorption of 4 cm³/g. Complex 1, which is constituted by a 鈥渟oft鈥?nonaromatic network that begins to collapse around 170 掳C, was subjected to controlled pyrolysis to produce CdO with morphology and phase selectivity. Texture of the thus obtained pure cubic phase of CdO (尾-form) was further tuned with the regulation of the annealing temperature. Crystals of rectangular blocks of [Cd(HL1L1)Cl]路2H₂O (2), which were formed in small quantity, feature a centrosymmetric, monoclinic space group (P2₁/c). Their crystal structure reveals a one-dimensional linear chain where Cd atoms are connected by a triple bridge made up of one 渭-chloride and two 渭-N1,N2-1,2,4-triazole HL1 and L1. The coordination polymer charge is balanced by both chloride and the carboxylate group of L1.