but2en2yl

But2en2yl refers to a hydrocarbon radical derived from butene. Specifically, it is a four-carbon chain with a double bond between the second and third carbon atoms, and the point of attachment to another molecule is at the second carbon. The chemical formula for this radical, when considered as a substituent, would be C4H7.

The but2en2yl group exists as two geometric isomers due to the double bond: cis-but2en2yl and trans-but2en2yl. The cis isomer has the larger substituent groups on the same side of the double bond, while the trans isomer has them on opposite sides. The nomenclature "but2en2yl" itself does not specify the cis or trans configuration and would typically be further qualified if referring to a specific isomer.

As a radical, but2en2yl is a reactive species with an unpaired electron. However, in the context of organic chemistry, it is more commonly encountered as a functional group or a substituent within larger molecules. For instance, it could be part of an alkene derivative or a more complex organic compound, influencing its chemical properties and reactivity. The presence of the double bond makes the molecule susceptible to addition reactions, while the branching at the second carbon can affect steric hindrance.

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