Development of Novel Type Reactions of Organotin Compounds Directed towards Organic Synthesis

由于锡原子与碳原子相比具有正电性，锡-碳键表现出作为碳负离子的反应性。然而，由于未经激发的锡-碳键是如此稳定，因此在与其他底物反应期间预期不会对反应性官能团产生明显干扰，从而使我们能够制备在同一分子内具有各种官能度的含锡化合物。在第二步反应中，通过对锡-碳键的控制，我们可以实现新型的锡化合物的典型反应，这些反应适用于合成目的。I和II所描述的试剂可以被视为双阴离子（III）或阴/阳离子（IV）等价物。我们开发了新的含锡试剂1-4作为有用的合成试剂。由此制备的锡化合物的反应类型取决于（1）同一分子内的官能团的性质，（2）官能团的活化方法，（3）锡-碳键与官能团之间的相对距离，和（4）辅助基团的存在。利用这些特点，我们开发了新型反应（6）-（8），并将这些反应应用于一些天然产物的合成。

Because of the electropositive character of the tin atom compared with that of carbon atom, the tin-carbon bond exhibits its reactivity as a carbanion. Since the unprovoked tin-carbon bond is so stable, however, no obvious interference with reactive functional groups is expected during the reaction with other substrates, thus allowing us to prepare tin-containing compounds having various functionalities within the same molecule. Upon manipulating the tin-carbon bond in the second-stage reaction, we can reallize novel types reactions typical of the tin-compounds, which are applicable for the synthetic purpose.The reagent depicted by I and II can be viewed as double anion (III) or anion/cation (IV) equivalents. We have developed new tin-containing reagents 1-4 as useful synthetic reagents. The reaction types of the tin compounds thus prepared are dependent upon (1) the nature of the functional groups within the same molecule, (2)the method of the activation of the functional groups, (3)relative distance between tin-carbon bond and the functional groups, and (4)the presence of the auxiliary groups. Utilizing these characteristics, we developed novel types reactions (6)-(8), and applied these reactions for the synthesis of some natural products.