From Competition to Commensuration by Two Major Hydrogen-Bonding Motifs

详细信息    查看全文

• 作者：Sihui Long ; Panpan Zhou ; Sean Parkin ; Tonglei Li
• 刊名：Crystal Growth & Design
• 出版年：2014
• 出版时间：January 2, 2014
• 年：2014
• 卷：14
• 期：1
• 页码：27-31
• 全文大小：258K
• ISSN：1528-7505

文摘

Carboxylic acid鈥揳cid hydrogen-bonding dimer and acid鈥損yridine hydrogen-bonding motif are two competing supramolecular synthons that a molecule possessing both carboxylic acid and pyridine functional groups could form in the solid state. Their coexistence has been observed but for the molecules with the molar ratio of carboxylic acid and pyridine groups being greater than 1:1. In this crystal engineering study, 2-[phenyl(propyl)amino]nicotinic acid with a 1:1 molar ratio of these two functional groups was discovered to have two polymorphs, in which one consists of unique hydrogen-bonded tetramer units bearing both acid鈥揳cid and acid鈥損yridine hydrogen-bonding motifs, while the other is composed of acid鈥損yridine hydrogen-bonded chains. Quantum mechanical calculations were employed to unravel the essence of the coexistence of the two vying counterparts as well as the origins of the tetramer and chain structures.