cis-2-Butene vs trans-2-Butene - Isomer Relationship

What is the relationship between cis-2-Butene and trans-2-Butene?

Same connectivity but different spatial arrangement around the C=C double bond. The methyl groups are on the same side (cis) or opposite sides (trans).

Molecule Acis-2-Butene (C₄H₈)
Molecule Btrans-2-Butene (C₄H₈)
Relationship Typecis-trans
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Introduction

Both molecules are 2-butene with the same connectivity. But the double bond prevents rotation — so how the groups are arranged matters.

Formula Comparison

Both have the formula C₄H₈ with the same atom connectivity: CH₃–CH=CH–CH₃.

Connectivity Analysis

The bonding sequence is identical in both molecules. Each has a C=C double bond between C2 and C3 with methyl groups on each end.

Spatial Relationship

In cis-2-butene, both CH₃ groups are on the same side of the double bond. In trans-2-butene, they are on opposite sides. The C=C double bond prevents rotation.

Chirality Check

Neither molecule has a tetrahedral chiral center. The restricted rotation around the double bond creates the isomerism.

Classification

These are cis-trans (geometric) isomers. Same connectivity, different spatial arrangement due to restricted rotation around the double bond.

Side-by-side 3D comparison with sync rotation, difference highlighting, and guided classification.

Compare cis-2-Butene and trans-2-Butene in 3D

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