Chemoselective Cleavage of Si-C(sp3) Bonds in Unactivated Tetraalkylsilanes Using Iodine Tris(trifluoroacetate)
Chemoselective Cleavage of Si-C(sp3) Bonds in Unactivated Tetraalkylsilanes Using Iodine Tris(trifluoroacetate)
复制标题
DOI：
10.1021/jacs.0c11645
复制
发表时间：
2021-01-13
影响因子：
15
通讯作者：
Matsunaga, Shigeki
中科院分区：
文献类型：
--
作者：
Matsuoka, Keitaro;Komami, Narumi;Matsunaga, Shigeki
有机硅烷是有机化学中有用的合成试剂和前体。然而，未活化的Si-C(sp(3))键在常规反应条件下的典型惰性阻碍了简单四烷基硅烷在有机合成中的应用。在此，我们报告了使用三（三氟乙酸）碘对未活化四烷基硅烷的 Si-C(sp(3)) 键进行化学选择性裂解。该反应在温和的条件下（-50℃至室温）顺利进行，并能耐受各种极性官能团，从而使得后续的Tamao-Fleming氧化能够提供相应的醇。反应的NMR实验和密度泛函理论计算表明，烷基从Si向I(II)中心的转移和Si-O键的形成协同进行，得到烷基-λ(3)-碘和三氟乙酸甲硅烷基酯。所开发的方法使得能够使用未活化的四烷基硅烷作为高度稳定的合成前体。
Organosilanes are synthetically useful reagents and precursors in organic chemistry. However, the typical inertness of unactivated Si-C(sp(3)) bonds under conventional reaction conditions has hampered the application of simple tetraalkylsilanes in organic synthesis. Herein we report the chemoselective cleavage of Si-C(sp(3)) bonds of unactivated tetraalkylsilanes using iodine tris(trifluoroacetate). The reaction proceeds smoothly under mild conditions (-50 degrees C to room temperature) and tolerates various polar functional groups, thus enabling subsequent Tamao-Fleming oxidation to provide the corresponding alcohols. NMR experiments and density functional theory calculations on the reaction indicate that the transfer of alkyl groups from Si to the I(II) center and the formation of the Si-O bond proceed concertedly to afford an alkyl-lambda(3)-iodane and silyl trifluoroacetate. The developed method enables the use of unactivated tetraalkylsilanes as highly stable synthetic precursors.