Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive MC 0358, La Jolla, CA, 92093, USA.
Angew Chem Int Ed Engl. 2017 Aug 28;56(36):10894-10899. doi: 10.1002/anie.201705877. Epub 2017 Jul 28.
The encumbered tetraisocyanide dianion Na [Fe(CNArMes2 ) ] reacts with two molecules of CO to effect reductive disproportionation to CO and carbonate ([CO ] ). When the reaction is performed in the presence of silyl triflates, reductive disproportionation is arrested by silylative esterification of a mono-CO adduct. This results in the formation of four-coordinate terminal iron carbynes possessing an aryl carbamate substituent owing to the direct attachment of an C(O)OSiR group to an isocyanide nitrogen atom. Crystallographic, spectroscopic, and computational analyses of these iron-carbon multiply bonded species reveal electronic structure properties indicative of a conformationally locked iron carbyne unit.
受阻碍的四异氰根合二价铁阴离子 Na [Fe(CNArMes2 ) ] 与两分子 CO 反应，通过还原歧化作用生成 CO 和碳酸盐 ([CO ] )。当反应在硅基三氟甲磺酸酯存在下进行时，还原歧化作用被一 CO 加合物的硅酯化酯化作用所阻止。这导致形成具有芳基氨基甲酸酯取代基的四配位末端铁卡宾，这是由于 C(O)OSiR 基团直接连接到异氰根氮原子上。这些铁-碳多重键合物种的晶体学、光谱学和计算分析揭示了电子结构特性，表明其具有构象锁定的铁卡宾单元。
