An unprecedented regioselective lithiation of dipyrromethanes. Synthesis of meso-functionalized dipyrromethanes
作者:Kamaljit Singh、Amit Sharma
DOI:10.1016/j.tetlet.2006.11.056
日期:2007.1
Functionalization of meso-positions of dipyrromethanes, gives valuable intermediates through a highly regioselective lithiation-substitution sequence. (c) 2006 Elsevier Ltd. All rights reserved.
Copper(ii)-catalyzed C–H (sp3) oxidation and C–N cleavage: synthesis of methylene-bridged compounds using TMEDA as a carbon source in water
作者:Dan Zhao、Yue Wang、Min-Xue Zhu、Qi Shen、Lei Zhang、Yun Du、Jian-Xin Li
DOI:10.1039/c3ra40695d
日期:——
A green, simple, and efficient protocol for the selective methylenation via CuCl2/oxygen-mediated CâH (sp3) oxidation and CâN cleavage using tetramethylethylenediamine (TMEDA) as a carbon source has been developed. The reactions were achieved in green solvent water under atmospheric conditions. The protocol exhibited a broad substrate scope including indoles, anilines, pyrroles and 1,3-dicarbonyls. Furthermore, two key intermediates of the reaction were successfully identified and the mechanism was explored.
Direct C–H Cyanation by ICN Formed <i>In Situ</i>: Nannozinone B
作者:Paul Wienecke、Hans-Dieter Arndt
DOI:10.1021/acs.orglett.3c00176
日期:2023.2.24
A novel method for C–H cyanation of different pyrans, pyrroles, indoles, and acyclic nucleophilic double bonds using TMSCN, NIS, and Zn(OTf)2 as a catalyst is described. The transformation is conducted under mild conditions tolerating a variety of functional groups. Zn(OTf)2 is likely to serve a dual catalytic role as an activator for TMSCN and for the cyanogen iodide generated in situ. Optimization