Cyclopropane

Cyclopropane is a cycloalkane molecule with the molecular formula C3H6 consisting of three carbon atoms linked to each other to form a ring, with each carbon atom bearing two hydrogen atoms. The bonds between the carbon atoms are a great deal weaker than in a typical carbon-carbon bond. This is the result of the 60° angle between the carbon atoms, which is far less than the normal angle of 109.5°. This ring strain has to be subtracted from the normal C-C bond energy, making the resultant compound more reactive than acyclic alkanes and other cycloalkanes such as cyclohexane and cyclopentane. This is the banana bond description of cycloalkanes.

Related Topics:
Cycloalkane - Molecule - Carbon - Atoms - Hydrogen - Compound - Alkane - Cycloalkanes - Cyclohexane - Cyclopentane - Banana bond

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However, cyclopropanes are more stable than a simple angle strain analysis would suggest. This is because the banana-bond model (without major tweaks) is incorrect; cyclopropane is better modeled as a three-center-bonded orbital combination of methylene carbenes. This results in the walsh orbital description of cyclopropane, where the C-C bonds have significant pi character. This is also why cyclopropanes often have reactivity similar to alkenes.

Related Topics:
Banana-bond - Three-center-bond - Carbenes - Walsh orbital - Alkene

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Boiling point: -32.8°C Freezing point: -127°C

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The naturally occurring pyrethrum insecticides (found in certain Chrysanthemum species) contain a cyclopropane ring.

Related Topics:
Pyrethrum - Insecticide - Chrysanthemum

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Cyclopropane is an anaesthetic when inhaled, but has been superceeded by other agents in modern anaesthetic practice. When the gas was mixed with oxygen there was significant explosion hazard.

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