X-Ray Analysis of Crystal Structure of Picrates of many kinds of Organic Compounds

苦味酸通过pi键或离子键与各种有机分子形成稳定的苦味酸盐，这类苦味酸盐在鉴定和定性分析中非常有用。但对它们的晶体结构的研究还很少。为了确定碱性化合物苦味酸盐的晶体结构和成键方式，我们对碱性有机化合物的晶体结构进行了系统的研究。我们测定了芳香烃(苯、间、对苯二胺)、氨基酸(甘氨酸)、药物(普鲁卡因)的苦味酸盐的晶体结构，结果表明，芳香烃的苦味酸盐是通过pi键形成的。苦味酸盐的氨基化合物主要是通过离子键形成的，但也有一部分是由pi-键和离子键共同形成的。

Picric acid forms stable picrates with various organic molecules through pi-bonding or ionic bonding, and such picrates have been very useful for identification and qualitative analysis. But there have been only a few studies on their crystal structures. As it desirable to determine the crystal structures and the bonding mode of picrates of basic compounds, we have syatematically investigated the crystal structures of basic organic compounds. We have determined crystal structures of picrate of aromatic hydrocarbon (benzene, omicron-, m-, p-phenylendiamine), amino acid(glycin), drug(procaine).From the above results, picrate of aromatic hydrocarbons are formed through pi-bonding. Picrates of amino compounds are mainly formed through ionic bonding, but some of them are formed by both pi- and ionic bondings.