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

Breaking bonds and breaking rules: [(iPr3P)Ni]5H4 as the key intermediate in cooperative C-H activation and carbon atom abstraction from alkenes and catalytic stereospecific dimerization of norbornene

“…This organic product was obtained as an oil by filtering the sample through a silica plug and identified as a single isomer of bis-2,2'norbornylidene by both 1 H and 13 C{ 1 H} NMR. This appears to be the first highly-selective norbornene dimerization catalyst, with previous Ni examples all requiring elevated temperatures and yielding mixtures of isomers [53][54][55] The mechanism likely features oxidative coupling of two norbornene molecules to 3, followed by C-H bond activation and reductive elimination to give the C2 product. In comparison, a solution of the mononuclear Ni(0) source [Ni( i Pr3P)2]2N2 and norbornene provided no catalysis.…”

Bayesian Optimized Oscillating Electric Heating of Dicyclopentadiene and Norbornene for Fuel Production

“…Hydrocarbon fuels with good low-temperature fluidity and high energy density are essential to expanding flight distance and increasing payload. − Tetracyclo­[6,2,1,0 2,7 ,1 3,6 ]­dodecene (TCD) with multiple bridge rings is a competitive candidate for developing new fuels owing to its good physicochemical and energy properties. − Using cyclopentadiene (CPD) and norbornene (NBE) as starting materials, TCD can be synthesized through the Diels–Alder reaction . NBE is readily available in industry, and it has an active double bond and unique bridge ring structure .…”

High-Energy-Density Liquid Spiro-Norbornanes from Methylenenorbornane

“…9−11 For example, JP-10 (exo-isomer of tetrahydrodicyclopentadiene) is the synthetic fuel that can give 13−14% more energy in comparison to distilled kerosene. 12−17 In recent years, various synthetic fuels have been developed, for instance, fully hydrogenated and isomerized tricyclopentadiene, 18,19 cyclopropanated terpenes, 20−22 alkyladamantanes, 23,24 hydrogenated dimers of norbornene and norbornadiene, 25,26 dimers of isoprene and myrcene, 27 etc.…”

“…The replacement of conventional jet fuels from petroleum refineries, such as kerosene, with synthetic ones has acquired particular relevance with the development of commercial, military, and space aviation because of their enhanced performance properties. − A synthetic jet fuel made from petrochemical or biohydrocarbon feedstocks has a significant advantage because it can be easily modified to suit current aircraft designs. Modern aircraft vehicles are often volume-limited, and the application of high-energy density fuels reduces fuel tank volumes, saving more space for useful components, or extending the maximum flight range without refueling. , In addition, liquid propellants used must also have suitable cryogenic properties such as low freezing points and viscosities to operate aircraft engines in harsh conditions. − For example, JP-10 ( exo -isomer of tetrahydrodicyclopentadiene) is the synthetic fuel that can give 13–14% more energy in comparison to distilled kerosene. − In recent years, various synthetic fuels have been developed, for instance, fully hydrogenated and isomerized tricyclopentadiene, , cyclopropanated terpenes, − alkyladamantanes, , hydrogenated dimers of norbornene and norbornadiene, , dimers of isoprene and myrcene, etc.…”