Chemoselective Hydrogenation of Ring‐Strained Monoterpenes: A Route to High‐Performance Sustainable Aviation Fuels

Sabinene and 3‐carene, bio‐based monoterpene precursors to high‐performance jet fuels, are chemoselectively hydrogenated with reduced PtO 2 at low temperatures (263–298 K), to yield products in which the alkene groups are saturated, whereas cyclopropane rings from the parent hydrocarbons are conserved. Sabinene is selectively converted to a 79:21 mixture of cis:trans‐thujane (1), whereas 3‐carene is converted to a 72:28 mixture of cis:trans‐carane (3). For comparison, the fully hydrogenated species tetrahydrosabinene (2) and 1,1,4‐trimethylcycloheptane ( 4 ) are prepared by hydrogenation with Pd/C. To evaluate 1−4 as advanced jet fuel blendstocks, several key fuel properties are measured. Compared with conventional jet fuel, the hydrogenated monoterpenes exhibit up to 8.6% higher density, 1.3% higher gravimetric net heat of combustion (NHOC), 9.7% higher volumetric NHOC, and 64% lower kinematic viscosity at −20 °C. These properties suggest that 1−4 are valuable blendstocks for conventional jet fuel or sustainable aviation fuel, providing enhanced operability and performance.