science

Fulvalene

Fulvalene is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Fulvalene rather than just read about it. In short: Fulvalene (bicyclopentadienylidene) is the member of the fulvalene family with the molecular formula C10H8. It is of theoretical interest as one of the simplest non-benzenoid conjugated hydrocarbons.

Key takeaways

Fulvalene belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Fulvalene to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Fulvalene from memory before moving on to harder problems.

Reference excerpt

Fulvalene (bicyclopentadienylidene) is the member of the fulvalene family with the molecular formula C10H8. It is of theoretical interest as one of the simplest non-benzenoid conjugated hydrocarbons. Fulvalene is an unstable isomer of the more common benzenoid aromatic compounds naphthalene and azulene. Fulvalene consists of two 5-membered rings, each with two double bonds, joined by yet a fifth double bond. It has D2h symmetry.

History

An earlier attempt at synthesis of fulvalene in 1951 by Pauson and Kealy resulted in the accidental discovery of ferrocene. Its synthesis was first reported in 1958 by E. A. Matzner, working under William von Eggers Doering. In this method, the cyclopentadienyl anion is coupled with iodine to the dihydrofulvalene. Double deprotonation of the dihydrofulvalene with n-butyllithium gives the dilithio derivative, which is oxidized by oxygen. Fulvalene was spectroscopically observed at −196 °C (77 K) from photolysis of diazocyclopentadiene, which induces dimerization of cyclopentadiene-derived carbenes. The compound was isolated in 1986 and was found to be nonaromatic. Above −50 °C (223 K) it dimerizes by a Diels–Alder reaction.

Derivatives Perchlorofulvalene (C4Cl4C)2 is quite stable in contrast to fulvalene itself.

See also Fulvenes, (CH=CH)2C=CH2 and substituted derivatives Tetrathiafulvalene, C2H2S2C=CS2C2H2 Tetramethyltetraselenafulvalene, C10H12Se4

References

Illustrations

Worked examples

Example 1 — a first encounter with Fulvalene

Start with the simplest possible case. Write down what Fulvalene claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Fulvalene before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Fulvalene ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Fulvalene

In research: Fulvalene appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Fulvalene in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Fulvalene is common in secondary-school and first-year university syllabi. It links to neighbouring topics Fulvalenes, Hydrocarbons, so understanding it makes those chapters shorter.
In everyday life: Look for Fulvalene outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Fulvalene in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Fulvalene means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Fulvalene out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Fulvalene in simple terms?

Fulvalene (bicyclopentadienylidene) is the member of the fulvalene family with the molecular formula C10H8. It is of theoretical interest as one of the simplest non-benzenoid conjugated hydrocarbons.

Why does Fulvalene matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Fulvalene?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Fulvalene.