New Lipophilic 2-Amino-<i>N</i>,<i>Nâ²</i>-dialkyl-4,5-dimethylimidazolium Cations: Synthesis, Structure, Properties, and Outstanding Thermal Stability in Alkaline Media
作者:Romanâ
A. Kunetskiy、Ivana CÃsarÌová、David SÌaman、Ilyaâ
M. Lyapkalo
DOI:10.1002/chem.200901203
日期:2009.9.21
A series of new N,N′‐dialkyl‐4,5‐dimethylimidazolium cations possessing electron‐rich 2‐imidazolylidene‐ or phosphoranylidene‐amino substituents has been efficiently synthesized from common precursors, N,N′‐dialkyl‐4,5‐dimethylimidazol‐2‐ylidenes. The new lipophilic salts obtained have been found to be highly stable towards strong alkali under both biphasic and homogeneous conditions. Their exceptional
一系列新Ñ,N'具有富电子-2- imidazolylidene-或磷亚基氨基取代二烷基-4,5-二甲基咪唑鎓阳离子已被有效地从共同的前体合成,Ñ,N' -二烷基-4,5-二甲基咪唑-2-亚基。已经发现,所获得的新亲脂盐在双相和均相条件下都对强碱高度稳定。迄今为止,它们仅在全烷基化的聚氨基磷氮鎓阳离子中才能见到的优异的耐碱性性能,可能归因于三个因素:芳族稳定,有效的共振电荷离域化和由于疏松的N导致的环外氮键的空间保护烷基取代基。