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碳阳离子、碳阴离子、自由基以及卡宾这些活性中间体在有机反应中起着重要的作用,为有机化学提供了极好的研究内容。在物理有机化学广泛开展的六十年代,活性中间体的研究更为活跃。但是由于这些中间体在游离状态下的活性太高,因此在和许多底物反应时不显示差别,而在要求高选择性或特异性的合成化学中不能作为使用物质。野依良治等有效地利用了金属元素的特性,既能提高活性中间体的稳定性,又能控制其反应性。例如,以碳-金属σ键结合的最简单的有机金属化合物R一M(1),可以得到烷基自由基,烷基阴离子,有时也可得到烷基阳离子的金属络合物,且能利用它们有目的地进行有机反应: R一M帐~we~)R一M十《-)R.。M(一)R+M- 1 由于这些络合物合成起来比较简单,又具有能保存等优点,所以是有机合成中的优良试剂。
Carbocations, carbanions, free radicals, and carbenes play an important role in organic reactions and provide excellent research on organic chemistry. In the sixties when the extensive development of physical organic chemistry, active intermediate research more active. However, since these intermediates are too active in the free state, they do not show any difference when they react with many substrates, and can not be used as synthetic substances in synthetic chemistry requiring high selectivity or specificity. Wild Yoshitsugu and other effective use of the characteristics of metal elements, both to improve the stability of the active intermediate, but also control their reactivity. For example, an alkyl radical, an alkyl anion, or a metal complex of an alkyl cation may be obtained from the simple organometallic compound R-M (1) which is bonded with a carbon-metal σ bond, They purposefully carry out organic reactions: R-M ~ we ~) R-M + "- R. M (a) R + M-1 Since these complexes are relatively simple to synthesize and have the advantages of being preserved, they are good reagents in organic synthesis.