研究室發表“從氮氣直接合成含氮有機化合物 ”綜述

從氮氣直接合成含氮有機化合物

李嘉鵬    殷劍昊    俞超    張文雄    席振峰*

化學學報 2017, 75, 733-743.（封面）（綜述）

( Acta Chim. Sinica 2017, 75, 733—743. )

作為與人類文明和生存密切相關的重大研究方向, 溫和條件下氮氣的活化與轉化（固氮）研究在1970-1990年代曾經是國際上備受關注的研究領域. 但是, 由于該領域極具挑戰性, 研究進展緩慢以及世界學術文化的變化, 進入21世紀以來從事相關基礎研究工作的化學研究者急劇減少. 然而, 毋庸置疑, 實現溫和條件下氮氣的活化與轉化是人類需要解決的重大科學問題, 是人類社會可持續發展的要求, 是科學家尤其是化學家最重要的使命之一. 将氮氣直接轉化為含氮有機化合物是氮氣的直接應用之一, 本文總結和歸納了文獻報道的金屬促進的以氮氣為原料直接生成含氮有機化合物的轉化方法和反應機理, 産物主要包括胺類, 酰胺類, 酰亞胺類, 腈類, 二氮烯類, 連氮類, 碳二亞胺類, 異氰酸酯類及雜環類有機化合物. 本文不包括将氮氣轉化成氨氣和部分還原及質子化産物的文獻.

Direct Transformation of N2 to N-Containing Organic Compounds

As a grand research area closely related to human civilization and living, the activation and transformation of dinitrogen (nitrogen fixation) under mild conditions used to be a central research theme worldwide in the 1970’s-1990’s. Nitrogen fixation is the process by which atmospheric nitrogen is directly converted to a bioavailable form. This basic chemical reaction process is essential to sustaining all life on this planet. However, due to great challenging of the nature of this research, slow progress and worldwide change of academic culture, the number of researchers engaged in this fundamental research area has been drastically reduced. Nevertheless, there is no doubt that realizing activation and transformation of dinitrogen under mild conditions is a grand scientific problem that people need to solve, required by sustainable development of human society. It is thus one of the most important missions of scientists, especially chemists. Three types of N-containing products can be obtained through direct transformation of dinitrogen. The most popular one is the formation of ammonia NH3 and NxHy. The industrial Haber-Bosch process, which requires harsh reaction conditions such as high temperature and pressure and uses at least 1-2% of the annual primary energy supply in the world, is still the main method to produce ammonia from molecular dinitrogen and dihydrogen gases. Inspired by the investigation of nitrogenase and the discovery of the first molecular nitrogen complex in 1965, chemists have paid more attention to achieving the reduction of dinitrogen to ammonia with transition metal complexes either as regents or as catalysts. Reports on the other two types of products, the N-E (E = P, Si) bonding compounds, and the N-C bonding compounds, are very rare. Compared with ammonia, nitrogen-containing organic compounds such as amines, amides, imides, amino acids and aza-heterocycles are also high-value products. This review mainly summarizes the progress in the field of direct transformation of molecular nitrogen to nitrogen-containing organic compounds by using transition metal complexes, as well as the elucidation of transformation mechanisms. The N-containing organic compounds thus formed include amines, amides, imides, nitriles, diazenes, azines, carbodiimides, isocyanates and heterocycles. Although some progress has been achieved, examples are still very much limited, efficiency is generally very low. Transition metal complex-catalyzed reaction process is in great demand. Synergetic strategy is considered to be one of the efficient ways to realize transition metal complex-catalyzed direct transformation of molecular nitrogen to nitrogen-containing organic compounds under mild conditions.

The formation of N-E (E = P, Si) bonding compounds and the reduction of dinitrogen to ammonia and other partially reduced or protonated products of dinitrogen are not covered here.