Highly Polymorphous Nicotinamide and Isonicotinamide: Solution versus Melt Crystallization
Highly Polymorphous Nicotinamide and Isonicotinamide: Solution versus Melt Crystallization
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DOI：
10.1021/acs.cgd.1c00547
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发表时间：
2021-07-21
影响因子：
3.8
通讯作者：
Shtukenberg, Alexander G.
中科院分区：
文献类型：
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作者：
Fellah, Noalle;Zhang, Carolyn Jin;Shtukenberg, Alexander G.
比较了烟酰胺（NA）及其结构异构体异烟酰胺（INA）的结晶过程。NA从熔体形成8种多晶型物，从溶液形成2种多晶型物，而INA从熔体形成2种多晶型物，从溶液形成6种。这一分析是由观察引起的，NA是高度多晶型的熔体，而密切相关的INA是高度多晶型的溶液。热台偏振光显微镜，粉末X-射线衍射，和拉曼光谱的组合显示，多晶型物的选择性是不相关的超分子自缔合在生长介质中。较大的估计的自由能隙分离NA多晶型物，与INA多晶型物相比，是一致的NA多晶型物从溶液中产生的数量较少。结晶动力学的现象学分析表明，交叉成核是最有可能的原因NA比INA从熔体中结晶的多晶型。
The crystallization of nicotinamide (NA) and its constitutional isomer, isonicotinamide (INA), is compared. NA formed eight polymorphs from the melt and two from solution, whereas INA formed two polymorphs from the melt and six from solution. This analysis was provoked by the observation that NA is highly polymorphic from the melt, while the closely related INA is highly polymorphous from solution. A combination of hot stage polarized light microscopy, powder X-ray diffraction, and Raman spectroscopy revealed that the polymorph selectivities are not related to supramolecular self-association in the growth media. The larger estimated free energy gap separating NA polymorphs, compared with that of the INA polymorphs, is consistent with the smaller number of NA polymorphs generated from solution. Phenomenological analyses of crystallization kinetics suggest that cross nucleation is the most likely reason more polymorphs of NA than INA crystallize from the melt.