2,2,2-Trifluorodiazoethane (CF₃CHN₂): A Long Journey since 1943

2,2,2-Trifluorodiazoethane (CF₃CHN₂) has been proven to be a valuable reagent for the rapid synthesis of various classes of trifluoromethyl-substituted organic molecules in both academic and industrial research. The reagent was prepared first in 1943, but only recently it received a great attention from the scientific community. Protocols for <i>in situ</i> generation, <i>in flow</i> generation, and crystalline analogues of CF₃CHN₂ were developed during the past decade and have led to an ever-increasing number of publications on the topic. The current review summarizes and comprehensively analyzes all manuscripts in a peer-reviewed literature on 2,2,2-trifluorodiazoethane since its discovery in 1943 until today (as of 19 June 2020). These include contributions mostly overseen by scientific community before. A particular emphasis of this review is to classify the existing reactivity modes of CF₃CHN₂ and to systematically analyze the corresponding reaction mechanisms in details. At the end of this review, several undeveloped areas for CF₃CHN₂ are outlined, based on the overseen precedents in the literature.