Propenyl
The term "propenyl" refers to a univalent radical or substituent with the molecular formula C3H5, derived from propene (CH3CH=CH2) by the removal of one hydrogen atom. It is an alkenyl group, meaning it contains a carbon-carbon double bond.
There are two main isomeric forms of propenyl, depending on which carbon atom the hydrogen is removed from:
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1-Propenyl (CH3CH=CH-): The double bond is directly attached to the carbon bearing the free valence. This isomer can exist as cis (Z) and trans (E) isomers due to the restricted rotation around the double bond.
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2-Propenyl (CH2=CHCH2-): Also known as allyl. The free valence is on the carbon adjacent to the double bond. The allyl group is resonance-stabilized, making it a common and reactive functional group in organic chemistry.
Propenyl groups are found in various organic compounds and are important intermediates in many chemical reactions. The specific properties and reactivity of a propenyl group depend on its isomeric form and the other substituents present in the molecule.