Hydrocarbon-soluble calcium hydride: A "Worker-Bee" in calcium chemistry
Hydrocarbon-soluble calcium hydride: A "Worker-Bee" in calcium chemistry
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DOI：
10.1002/chem.200701028
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发表时间：
2007-01-01
影响因子：
4.3
通讯作者：
Harder, Sjoerd
中科院分区：
文献类型：
--
作者：
Spielmann, Jan;Harder, Sjoerd
研究了碳氢化钙配合物[{CAH(dipp-nacnac)(THF)}(2)](1；dipp-nacnac=CHI{(CME)(2，6-iPr2-C6H3N)}(2))与多种底物的反应活性。将I加到C=O和C=N官能团上，可以很容易地得到醇钙和酰胺络合物。类似地，氰化物或异氰化物中的C相当于N键的还原分别得到了第一个缩醛钙络合物[Ca{N=C(H)-R}(dipp-nacnac)]和[Ca{C(H)-NR}-(dipp-nacnac)]。1与硼烷或丙烷路易斯酸络合，得到了接触离子对的硼酸盐和丙酸酯。在与环氧化物的反应中，亲核开环是主要反应。烃可溶的1与大多数官能团的高反应性与不溶的CaH2形成了强烈的对比，后者基本上是惰性的，被用作常见的干燥剂。晶体结构如下：[{Ca{OC(H)Ph-2}(dipp-nacnac)}(2)]，[{Ca{N=C(H)Ph)(dipp-nacnac)}(2)]，[{Ca{C(H)=NC(Me)(2)CH2C-(Me)(3)}(dipp-nacnac)}(2)]，[(Ca{C(H)=NCyl(dipp-nacnac)}(2)][Ca(dipp-nacnac)(THF)](+)[H2BC8H14](-)和[{Ca(Ocy)(dipp-nacnac)}(2)])。I与多种底物的转化通常是平稳和清洁的，而且大多数中间体对配体交换的稳定性使I成为合成多种β-二酮酸钙络合物的重要前驱体。
The reactivity of the hydrocarbon-soluble calcium hydride complex [{CaH(dipp-nacnac)(thf)}(2)] (1; dipp-nacnac =CHI{(CMe)(2,6-iPr2- C6H3N)}(2)) with a large variety of substrates has been investigated. Addition of I to C=O and C=N functionalities gave easy access to calcium alkoxide and amide complexes. Similarly, reduction of the C equivalent to N bond in a cyanide or an isocyanide resulted in the first calcium aldimide complexes [Ca{N=C(H)-R}(dipp-nacnac)] and [Ca{C(H)-NR}-(dipp-nacnac)], respectively. Complexation of 1 with borane or alane Lewis acids gave the borates and alanates as contact ion pairs. In reaction with epoxides, nucleophilic ring-opening is observed as the major reaction. The high reactivity of hydrocarbon-soluble 1 with most functional groups contrasts strongly with that of insoluble CaH2, which is essentially inert and is used as a common drying agent. Crystal structures of the following products are presented: [{Ca{OC(H)Ph-2}(dipp-nacnac)}(2)], [{Ca{N=C(H)Ph)(dipp-nacnac)}(2)], [{Ca{C(H)=NC(Me)(2)CH2C-(Me)(3)}(dipp-nacnac)}(2)], [(Ca{C(H)= NCyl(dipp-nacnac)}(2)] [Ca(dipp-nacnac)(thf)](+)[H2BC8H14](-) and [{Ca(OCy)(dipp-nacnac)}(2)]. The generally smooth and clean conversions of I with a variety of substrates and the stability of most intermediates against ligand exchange make I a valuable key precursor in the syntheses of a wide variety of beta-diketiminate calcium complexes.