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Chirality (/ k aɪ ˈ r æ l ɪ t i /) is a property of asymmetry important in several branches of science. The word chirality is derived from the Greek χείρ (kheir), "hand", a familiar chiral object. An object or a system is chiral if it is distinguishable from its mirror image; that is, it cannot be superposed (not to be confused with ...
In the achiral molecules, X and Y (with no subscript) represent achiral groups, whereas X R and X S or Y R and Y S represent enantiomers. Note that there is no meaning to the orientation of an S 2 axis, which is just an inversion. Any orientation will do, so long as it passes through the center of inversion.
A chirality center (chiral center) is a type of stereocenter. A chirality center is defined as an atom holding a set of four different ligands (atoms or groups of atoms) in a spatial arrangement which is non-superposable on its mirror image. Chirality centers must be sp 3 hybridized, meaning that a chirality center can only have single bonds. [5]
A general definition of chirality based on group theory exists. [2] It does not refer to any orientation concept: an isometry is direct if and only if it is a product of squares of isometries, and if not, it is an indirect isometry. The resulting chirality definition works in spacetime. [3] [4]
A chirality center is also called a chiral center [16] [17] [18] or an asymmetric center. [19] Some sources use the terms stereocenter , stereogenic center , stereogenic atom or stereogen to refer exclusively to a chirality center, [ 16 ] [ 18 ] [ 20 ] while others use the terms more broadly to refer also to centers that result in diastereomers ...
Absolute configuration is typically relevant in organic molecules where carbon is bonded to four different substituents. This type of construction creates two possible enantiomers . Absolute configuration uses a set of rules to describe the relative positions of each bond around the chiral center atom.
The simplest chiral knot is the trefoil knot, which was shown to be chiral by Max Dehn. All nontrivial torus knots are chiral. The Alexander polynomial cannot distinguish a knot from its mirror image, but the Jones polynomial can in some cases; if V k (q) ≠ V k (q −1), then the knot is chiral, however the converse is not true.
Chiral inversion is the process of conversion of one enantiomer of a chiral molecule to its mirror-image version with no other change in the molecule. [1] [2] [3] [4]Chiral inversion happens depending on various factors (viz. biological-, solvent-, light-, temperature- induced, etc.) and the energy barrier energy barrier associated with the stereogenic element present in the chiral molecule. 2 ...