The structure of vitamin A is shown in Problem 4.54. Is the double bond nearest the ring on the carbon chain cis or trans?

Verified step by step guidance

1. Examine the structure of vitamin A provided in Problem 4.54, focusing on the double bond nearest the ring on the carbon chain.
2. Identify the two groups attached to each carbon atom of the double bond. Recall that a double bond consists of two carbon atoms, each bonded to two other groups.
3. Determine the spatial arrangement of the groups around the double bond. In a cis configuration, the two larger or similar groups on each carbon are on the same side of the double bond. In a trans configuration, they are on opposite sides.
4. Compare the positions of the groups attached to the double bond nearest the ring. Look for whether the groups are aligned on the same side (cis) or opposite sides (trans).
5. Conclude whether the double bond nearest the ring is cis or trans based on the spatial arrangement of the groups identified in the previous step.

Key Concepts

Cis-Trans Isomerism

Cis-trans isomerism refers to the geometric configuration of molecules with restricted rotation around a double bond. In cis isomers, substituents are on the same side of the double bond, while in trans isomers, they are on opposite sides. This distinction can significantly affect the physical and chemical properties of the compound.

Structure of Vitamin A

Vitamin A, also known as retinol, has a complex structure that includes a long carbon chain and a cyclic component. Understanding its structure is crucial for identifying the configuration of double bonds within the molecule. The arrangement of atoms and functional groups influences its biological activity and interactions.

Double Bond Configuration

The configuration of a double bond in organic chemistry can be classified as either cis or trans based on the relative positions of the substituents attached to the carbon atoms involved in the double bond. Identifying this configuration is essential for predicting the behavior and reactivity of the molecule, particularly in biological systems.