Stereochemistry: Absolute Configuration and Naming

<p>Different compounds with the same name (A)</p> Signup and view all the answers

<p>They are defined based on the direction of light rotation. (B)</p> Signup and view all the answers

<p>The circle progresses clockwise. (A)</p> Signup and view all the answers

<p>The designation is reversed. (D)</p> Signup and view all the answers

<p>8 (B)</p> Signup and view all the answers

<p>More chiral centers increase the number of potential stereoisomers exponentially. (D)</p> Signup and view all the answers

<p>4 (C)</p> Signup and view all the answers

<p>It is named when the circle is traced counterclockwise. (A)</p> Signup and view all the answers

<p>Flying wedge diagrams. (D)</p> Signup and view all the answers

<p>Using the equation $2^4$. (A)</p> Signup and view all the answers

<p>Reverse the configuration from R to S. (D)</p> Signup and view all the answers

<p>They are non-superimposable and non-mirror images. (D)</p> Signup and view all the answers

<p>One stereoisomer is identical to its mirror image. (C), It contains a meso compound. (D)</p> Signup and view all the answers

<p>They are achiral compounds with multiple stereogenic centers. (D)</p> Signup and view all the answers

<p>The solution is optically inactive. (B)</p> Signup and view all the answers

<p>Two optically active isomers. (B)</p> Signup and view all the answers

<p>It contains stereogenic centers that are superimposable on their mirror images. (D)</p> Signup and view all the answers

<p>Four stereoisomers. (A)</p> Signup and view all the answers

<p>Cis isomers have groups on the same side of the double bond. (A)</p> Signup and view all the answers

<p>It is rigid and holds attached groups in fixed positions. (C)</p> Signup and view all the answers

<p>Higher ranked substituents on opposite sides. (C)</p> Signup and view all the answers

<p>Cis-2-Butene (A)</p> Signup and view all the answers

<p>Different spatial arrangements around a double bond. (B)</p> Signup and view all the answers

<p>Ability to interconvert by simple rotation. (A)</p> Signup and view all the answers

<p>Identical substituents can lead to both cis and trans isomers. (D)</p> Signup and view all the answers

<p>Cis represents substituents on the same side. (A)</p> Signup and view all the answers

A system to uniquely determine the arrangement of atoms around a chiral center.

Describes how a substance rotates polarized light; clockwise (dextrorotatory) or counterclockwise (levorotatory).

A method to name and distinguish enantiomers (molecules that are non-superimposable mirror images).

Non-superimposable mirror images of each other; different molecules despite similar structure.

An atom with four different groups bonded to it; often a carbon atom. Essential in determining chirality.

A system used to assign a specific name (R or S) to a chiral center based on the arrangement of atoms or groups attached to it. It relies on priority rules and a clockwise/counterclockwise direction.

A way to represent a 3D molecule in 2D. It shows the chiral center at the intersection of vertical and horizontal lines, with groups projecting out of the plane.

An atom, usually carbon, with four different groups or atoms attached to it. It creates a non-superimposable mirror image, leading to stereoisomers.

Molecules with the same molecular formula and connectivity but different spatial arrangements of atoms. They have diverse physical and chemical properties.

In the R/S system, a clockwise direction of priority groups around the chiral center is assigned 'R', while a counterclockwise direction is assigned 'S'.

The Cahn-Ingold-Prelog priority rules assign a priority number (1, 2, 3, 4) to each group attached to a chiral center based on atomic number. Higher atomic number = higher priority.

For a molecule with 'n' chiral centers, the maximum number of stereoisomers possible is 2^n.

A representation of a molecule in 3D space, where solid wedges depict bonds coming out of the plane of the paper, and dashed wedges represent bonds going into the plane.

A diastereomer is a stereoisomer that is not a mirror image of another stereoisomer. They are non-superimposable and have different physical properties.

A meso compound is an achiral molecule that contains chiral centers. It has an internal plane of symmetry, making it superimposable on its mirror image.

2,3-dibromobutane only has three stereoisomers, not four, because one of the stereoisomers is superimposable on its mirror image. This superimposable stereoisomer is a meso compound.

Tartaric acid has two chiral centers, so it should have four possible stereoisomers. However, two of these isomers are identical, leaving three distinct isomers. One of these isomers is a meso compound due to its internal plane of symmetry, leaving only two optically active enantiomers.

A racemic mixture is an equal mixture of two enantiomers. It is optically inactive because the rotations of the enantiomers cancel each other out.

The R/S system is a method for assigning absolute configurations to enantiomers. 'R' and 'S' designate the chirality of a chiral center based on the priority of the groups attached to it.

When a group is on the horizontal line in a Fisher projection, it is considered 'on top'. If this group is number 4, we need to switch the configuration from what it initially appears to be.

Drawing different isomers in Fischer projections involves selectively switching the groups on the horizontal line. Reversing all groups on the horizontal line produces the first isomer. Reversing only ONE group on the horizontal line gives the third isomer, and so forth.

Isomers with the same atoms but different spatial arrangement due to restricted rotation across a double bond. They are also called geometrical isomers.

A cis isomer has two groups attached to the same side of a double bond.

A trans isomer has two groups attached to opposite sides of a double bond.

Constitutional isomers have different connectivities of atoms, while cis/trans isomers have the same connectivity but differ in spatial arrangement around a double bond.

A system used to describe the configuration of double bonds, specifically when there are more than two substituents on the double bond.

Higher priority substituents on opposite sides of the double bond.

Higher priority substituents on the same side of the double bond.

Cahn-Ingold-Prelog (CIP) priority rules are used to determine the priority of substituents on a double bond. Higher atomic number has higher priority.