Date of Award


Document Type

Honors Thesis (Open Access)


Colby College. Chemistry Dept.


Dasan M. Thamattoor

Second Advisor

Reuben H. Hudson


This thesis examines the generation of 2-adamantylidenecarbene from a phenanthrene-based precursor. A three-step synthetic procedure was used to generate the 2-adamantylidenecarbene precursor, which subsequently underwent photolysis to produce 2-adamantylidenecarbene. This product was trapped with cyclohexene. No evidence of a ring expansion to 4-homoadamantyne was observed. It was also noted that the target precursor underwent rearrangement during photolysis, leading to the formation of an isomer containing a seven-membered ring. This isomer did not photolyze. Additionally, computational studies were performed using Gaussian 09. Geometries were initially optimized and then, the single point energies of the singlet and triplet carbene states were calculated. It was found that the singlet 2-adamantylidenecarbene is energetically more stable. Finally, the transition barrier between the singlet 2-adamantylidenecarbene and 4-homoadamantyne was calculated to be 24.8 kcal/mol.


carbene, photolysis, phenanthrene, adamantylidenecarbene, Petasis reaction