mathematics

Thioketene

Thioketene is a mathematics 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 Thioketene rather than just read about it. In short: In organic chemistry, thioketenes are organosulfur compounds analogous to ketenes with the general formula R2C=C=S, where R is alkyl or aryl. The parent thioketene (ethenethione) has the formula CH2=C=S.

Key takeaways

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

Reference excerpt

In organic chemistry, thioketenes are organosulfur compounds analogous to ketenes with the general formula R2C=C=S, where R is alkyl or aryl. The parent thioketene (ethenethione) has the formula CH2=C=S. It is the simplest thioketene. Ethenethione is stable as a gas, but like most thioketenes, it polymerizes upon condensation.

Synthesis Thioketones may be prepared by treatment of acid chlorides with phosphorus pentasulfide as described by the following idealized equation:

RR'CHC(O)Cl + P4S10 → RR'C=C=S + HCl + "P4S9O" Some thioketenes are produced as transient species upon pyrolysis of 1,2,3-thiadiazoles. Elimination from α-chloroalkenyl thiolates RR'C=C(Cl)S− also yields thioketenes. These intermediates are believed to be responsible for the cytotoxicity and mutagenicity of trichloroethylene, as well as certain other polyhalogenated alkenes, with toxication occurring via conjugation with glutathione.

Isolable thioketenes Thioketenes can be stabilized by either steric protection or by electronic effects. Thus, di-tert-butyl thioketene is easily isolated and air-stable. Several examples have been characterized by X-ray crystallography. The C=S distance is 157 pm and the C=C distance is 124 pm, both bonds being suitable for the C=C=S assignment. The violet color characteristic of thioketenes indicates the small HOMO–LUMO gap. Bis(trifluoromethyl)thioketene ((CF3)2C=C=S) is an example of an electronically stabilized thioketene.

Reactions Thioketenes are electrophilic. They add amines to give thioamides:

R2C=C=S + HNR'2 → R2CH−C(S)−NR'2 With peroxyacids, they produce thioketene-S-oxides:

R2C=C=S + R'CO3H → R2C=C=S=O + R'CO2H Thioketenes bind to metal carbonyls giving adducts.

Related compounds carbon subsulfide (S=C=C=C=S).

References

Illustrations

Worked examples

Example 1 — a first encounter with Thioketene

Start with the simplest possible case. Write down what Thioketene claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In mathematics, 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 Thioketene 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 Thioketene 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 Thioketene

In research: Thioketene appears in mathematics 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 Thioketene 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: Thioketene is common in secondary-school and first-year university syllabi. It links to neighbouring topics Functional groups, Heteroallenes, Ketenes, so understanding it makes those chapters shorter.
In everyday life: Look for Thioketene 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.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Thioketene” →

Affiliate

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

How to study Thioketene in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Thioketene 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 Thioketene out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Thioketene in simple terms?

Why does Thioketene matter?

Because it connects several mathematics 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 Thioketene?

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 Thioketene.