Isomerism and hybridization
暂无描述。系统推荐的高质量记忆内容，适合每天坚持背诵学习。
卡片预览 (24 张)
what is stereochemistry?
the study of molecules as 3D structures
what is a mirror image?
the reflection of an object in a mirror
what is chirality?
an object and its mirror image are nonsuperposable
what is achirality?
an object that lacks chirality; an object and its mirage image are superposable
What makes an object achiral?
If it has one or more element of symmetry
What are two (2) examples of elements of symmetry?
• Plane of symmetry 2. Center of symmetry
What is a plane of symmetry?
An imaginary plane passing through an object dividing it so that one half is the mirror image of the other half
What is a center of symmetry?
A point situated so that for all atoms in a molecule, an identical atom lies on opposite sides and equidistant from that point.
What is the simplest way to determine if an object is chiral?
If an object has no element of symmetry it is chiral.
What are stereoisomers?
Isomers that have the same molecular formula and connectivity but a different orientation of their atoms in space.
What is a conformational isomer?
Isomers that can be interconverted exclusively by rotations about a single bond.
What is a configurational isomer?
Isomers that have the same connectivity of atoms but the attached atoms are in different positions.
What is an enantiomer?
Stereoisomers that are nonsuperposable mirror images (i.e. chiral objects) of each other.
What is the difference between the terms “chiral” and “enantiomers?”
“Chirality” is a characteristic of objects while “enantiomers” refers to a relationship between a pair of objects.
What is a chiral center?
A tetrahedral atom (usually carbon) bonded to four different groups.
What is the most common cause of chirality in organic molecules?
A chiral center
What is a stereocenter and what is a specific type of stereocenter?
An atom about which exchange of two groups produces a stereoisomer. (For example, the carbons bonded to two groups to form cis,trans isomers.) Chiral centers are a type of stereocenter.
What two types of objects can comprise configurational isomers?
• Chiral 2. Achiral
What is it called when a pair of configurational isomers are chiral objects?
Enantiomerism
What’s an example of of a pair of configurational isomers that are achiral objects?
Some cis,trans isomers (ex. 1,4-dimethylcyclohexane)
What is cis,trans isomerism?
Isomerism that exists because of restricted rotation about a double bond.
What is a diastereomer?
Stereoisomers that are not mirror images of each other.
What will cause diastereomerism?
Two or more stereocenters in a molecule.
Why are conformational isomers considered stereoisomers?
Because the atoms are arranged differently in space.