School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology , Wuhan 430070, People's Republic of China.
Department of Chemistry, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States.
J Am Chem Soc. 2017 Jan 18;139(2):888-896. doi: 10.1021/jacs.6b11188. Epub 2017 Jan 9.
Pd-catalyzed C-H functionalizations promoted by transient directing groups remain largely limited to C-H arylation only. Herein, we report a diverse set of ortho-C(sp)-H functionalizations of benzaldehyde substrates using the transient directing group strategy. Without installing any auxiliary directing group, Pd(II)-catalyzed C-H arylation, chlorination, bromination, and Ir(III)-catalyzed amidation, could be achieved on benzaldehyde substrates. The transient directing groups formed in situ via imine linkage can override other coordinating functional groups capable of directing C-H activation or catalyst poisoning, significantly expanding the scope for metal-catalyzed C-H functionalization of benzaldehydes. The utility of this approach is demonstrated through multiple applications, including late-stage diversification of a drug analogue.
Pd 催化的瞬态导向基团促进的 C-H 功能化反应在很大程度上仍然仅限于 C-H 芳基化反应。在此，我们报告了使用瞬态导向基团策略对苯甲醛底物进行的一系列不同的邻位 C(sp)-H 功能化反应。在不安装任何辅助导向基团的情况下，通过亚胺键原位形成的瞬态导向基团可以克服其他能够导向 C-H 活化或催化剂中毒的配位官能团，显著扩展了苯甲醛的金属催化 C-H 功能化反应的范围。该方法的实用性通过多种应用得到了证明，包括药物类似物的后期多样化。
