Bullvalene is an unusual organic molecule with a cage-like structure formed by the fusion of one cyclopropane and three cycloheptadiene rings. It has the chemical formula C10H10 and is notable for its C-C and C=C bonds forming and breaking rapidly on NMR due to multiple and fast degenerated Cope rearrangements. The document discusses the discovery, synthesis, structure, stereodynamics, physical properties, and related compounds of bullvalene.

1. BULLVALENE
BY
T.Ramkumar
Roll No:19PGCH10
CLASS:1ST M.Sc CHMEISTRY
Guide by
Dr.M.Saravanakumar
Assistant professor
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2. INTRODUCTION
• Bullvalene is a hydrocarbon with chemical formula is C10H10.
• The molecule has a cage-like structure formed by the fusion of
one cyclopropane and three cycloheptadiene rings.
• Bullvalene is unusual as an organic molecule due to the C-C and
C=C bonds forming and breaking rapidly on the NMR
• In bullvalene all C–C bonds are in continuous movement due to
multiple and fast degenerated Cope rearrangements
• It is a structure that is part of the fluctional molecules
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3. Structure
IUBAC Name
• Tricyclo[3.3.2.02,8]deca-3,6,9-
triene
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4. Synthesis of Bullvalenes
• This molecule was serendipitously obtained in 1963 by
Schröder and co-workers while exploring the
photochemistry of cyclooctatetraene dimers. Despite the
low overall yield (6%), this two-step synthesis of
bullvalene (1),
• The dimerization of cyclooctatetraene (2) at 100 °C and
subsequent photochemical opening of the dimer(3)
(Scheme 1) with the consequential formation of benzene
as byproduct
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5. The first synthesis of bullvalene (Schröder and
co-workers)
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6. another synthesis
• In 1966, the von Doering group developed a different
synthetic strategy for the preparation of bullvalene
(1) vie the UV irradiation of 4a,8a-
dihydronaphthalene (5), prepared by thermal
partial decomposition of the Nenitzescu hydrocarbon
(4) at 301 °C
• this synthesis was impractical due to the formation
of naphthalene and other undetermined products
that were difficult to separate from 1 (Scheme 2).
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7. Scheme 2 Synthesis of bullvalene (von Doering
group)
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8. Stereodynamics
• The bullvalene molecule is a cyclopropane platform
with three vinyl arms conjoined at a methine group
• As a fluxional molecule,bullvalene is subject to
degenerate cope rearrangements,with the result that
all carbon atoms and hydrogen atoms appear
equivalent on the NMR timescale
• The number of possible valence tautomers is 1,209,600
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9. Five of the bullvalene tautomers and some Cope
rearrangements between them.
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10. 10

11. Physical Properties
Chemical formula C10H10
Molar mass 130.19 g/mol
Melting point 96 °C (205 °F; 369 K)
Boiling point
decomposition at about 400 °C (752 °F;
673 K)
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12. Related compounds
• Bullvalones
• Semibullvalene(C8H8)
• Barbaralane
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13. Reference
1. I.L.Finer, Organic chemistry.
2. J.March, Advanced organic chemistry.
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