Scott LT,
Hashemi MM,
Meyer DT,
Warren HB.
University of Nevada, Reno, USA
Corannulene. A Convenient New Synthesis.
J. Am. Chem. Soc. 1991;
113: 7082-7084
DOI:
10.1021/ja00018a082
Key words
corannulene - hydrocarbon synthesis - Corey–Fuchs reaction - flash vacuum pyrolysis - vinylidene C–H insertion
Significance
Corannulene is a polycyclic aromatic hydrocarbon consisting of a cyclopentane ring that is fused with five benzene rings. The bowl-shaped molecule was first synthesized by Bath and Lawton in 1966 (J. Am. Chem. Soc.
1966, 88, 380). In 1991, Scott and co-workers presented a simplified synthesis featuring flash vacuum pyrolysis to access the product.
Comment
Knoevenagel condensation and Diels–Alder cycloaddition give access to tetracyclic diester F. The corresponding aldehyde G is then converted in a Corey–Fuchs reaction to dialkyne I. Flash vacuum pyrolysis putatively furnishes vinylidene J which is trapped to yield corannulene. Interestingly, gem-dibromoalkene H also yields corannulene under flash vacuum pyrolysis conditions by loss of bromine atoms.
