2,2,2-Trifluorodiazoethane (CF3CHN2): A Long Journey since 1943
Chem. Rev. 2020, 120 (22), 12718-12755
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 in situ generation, in flow 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.