A simple dehydrazination reaction has been achieved in the presence of a catalytic amount of CuSO4 for the first time. With CuSO4 (2 mol%) as a catalyst and water as a solvent, the dehydrazination products were obtained in good yields (66–95%). Moreover, the drugs nebularine and vidarabine were afforded successfully, and vidarabine could be produced on a 0.923 kg scale, which shows good potential for industrial applications.
A mild and practical protocol for highly regioselective C6−Halkylation of purines with alcoholsintervened by oxalates under blue LED irradiation is reported. This transformation does not need transition metalcatalysts, is not sensitive to moisture and does not require N2 protection. Besides, this method displays broad functional groups compatibility and is easily scale up.
报告了一种温和实用的方案,用于在蓝色 LED 照射下草酸盐干预嘌呤与醇的高度区域选择性 C6-H 烷基化。这种转化不需要过渡金属催化剂,对水分不敏感,也不需要N 2保护。此外,该方法显示出广泛的功能组兼容性并且易于放大。
Metal-free, direct acylation of purines to access C<sup>6</sup>-acylated purine derivatives induced by TBHP <i>via</i> Minisci-type reaction
A metal-free C–H functionalization of purines with aldehydes was developed to access C6-acylated purines via green radical reactions. Theoretically, there are many competitive reactions due to the three C–H bonds (C2–H, C6–H, C8–H) in the purine, and the acylation only happens at the purinyl C6-position. This method avoids a metal catalyst and provides a green approach to construct C–C (sp2) bonds