Catalytic dimerization of norbornadiene and norbornene into hydrocarbons with multiple bridge rings for potential high-density fuels

High-density hydrocarbon fuels are essential for air craft to increase payload and expand flight distance. This review will summarize the synthesis of high-density hydrocarbon molecules through catalytic dimerization of norbornadiene and norbornene in the past few decades, which can be used as new fuels or high-energy additives for conventional fuels. Dimerization of norbornadiene including relationship between structural dimers and investigation on metal based homogeneous catalysts and heterogeneous catalysts as well as description of possible mechanisms are firstly introduced. Then synthesis of multicyclic compounds from norbornene is illustrated with a focus on efficient and greener routes. After that, physicochemical properties of partial norbornadiene and norbornene dimers and influence of the composition on fuel performance are reviewed. Finally, we will propose the problems in synthesis of high-energy-density fuel through dimerization of norbornene and norbornadiene. This review will be helpful to explore new approaches to synthesize more valuable high-density hydrocarbon fuels and predict possible directions of synthesizing new multi-cyclic hydrocarbon compounds with norbornadiene and norbornene. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

This review summarizes the research on the synthesis of high-density hydrocarbon molecules through the catalytic dimerization of norbornadiene and norbornene in the past few decades. The review discusses the relationship between structural dimers, various catalysts, possible mechanisms, and the synthesis of multicyclic compounds from norbornene. Additionally, it reviews the physicochemical properties of dimers and the influence of composition on fuel performance, as well as proposing challenges in synthesizing high-energy-density fuels through dimerization.