Week 8 Flashcards
it is the chemistry of space
stereochemistry
Stereochemistry is a branch of chemistry that involves the study of the different _________ of atoms in molecules
spatial arrangement
it refers to the 3-dimensional arrangement of atoms
stereochemistry
the same order but different intrinsic shape
stereoisomer
(True or False)
Chiral is superimposable (identical) on its mirror image
False
(achiral)
(True or False)
Chiral is not super imposable (not identical on its mirror image
True
(True or False)
The most common source of molecular chirality is the presence of carbon atom bearing 3 different groups
False
(4 different groups)
In 1996, the IUPAC recommended that a tetrahedral carbon bearing 4 different groups be called
chirality center
Other names for chirality center
chiral center, stereocenter, stereogenic center and asymmetric center
(True or False)
CH2 and CH3 can be tetrahedral stereogenic centers
False
(more than one H bonded to C)
(True or False)
Any sp or sp2 hybridized C can be tetrahedral stereogenic centers
False
(less than four groups around C)
is bronchidilator that widen airways so it is used to treat asthma
Albuterol
is an antibiotic used extensively in developing countries because of its low cost
chloramphenicol
same chemical formula but different structures
isomers
isomers that have different connectivity
constitutional isomers
isomers that have the same connectivity but different spatial arrangement (configuration)
stereoisomers
mirror-image isomers
enantiomers
non-mirror image isomers
diastereomers
2 types of diastereomers
configurational and cis-trans
(True or false)
Constitutional isomer can have the same IUPAC names
False
(different IUPAC name)
(True or false)
Constitutional isomer have different physical and chemical properties
True
Constitutional isomer have similar or different functional groups
True
(True or false)
Constitutional isomer have different formula and connectivity
False
(same molecular formula)
are compounds whose atoms are connectivity in the same order but with a different spatial arrangement
Stereoisomers
these are nonsuperimposable mirror-image (chiral) stereoisomer
enantiomers
these are nonsuperimposable non-minor image stereoisomer
diastereomers
Test for chirality
(1) Presence of a single chirality center
(2) plane of symmetry
(True or False)
A molecule will be chiral if it possesses a plane of symmetry
False
(will not be chiral)
A plane symmetry also called
mirror plane
Defined as an imaginary plane that bisects a molecules in a way that the two halves of the molecule are mirror images of each other
plane symmetry
(True or False)
All molecules with a plane of symmetry in their most symmetrical conformation are achiral
True
anti inflammatory agent
(S)-naproxen
liver toxin
(R)- naproxen
(True or False)
When naming a chiral compound, the configuration of the chirality center is indicated at the beginning of the name, italicized, and surrounded by parentheses
True
(True or False)
When multiple chirality centers are present, each configuration must be preceded by a locant (a number) to indicate its location on the parent chain
true
Pure enantiomers have ________melting and boiling points
identical
(True or False)
Enantiomers show the same behavior only when they interact with other chiral substances, including their own enantiomer
false
(different)
When a beam of plane-polarized light passes through an enantiomer, the plane of polarization _______.
rotates
(True or False)
Separate enantiomers rotate the plane of plane-polarized light equal amounts but in same directions
false
(opposite)
is an electromagnetic phenomenon
light
A beam of light consists of two mutually perpendicular oscillating fields:
oscillating electric field
oscillating magnetic field
The device that is used for measuring the effect of optically active compounds on plane-polarized light is a
polarimeter
principal working parts of a polarimeter are
(1) light source
(2) polarizer
(3) cell
(4) analyzer
(5) scale
a light source is usually a
sodium lamp
for holding the optically active substance (or solution) in the light beam
cell
for measuring the angle (in degrees) that the plane of
polarized light has been rotated
scale
(Direction of rotation)
left or counterclockwise
levorotatory(-)
(Direction of rotation)
right or clockwise
dextrorotatory(+)
He is the father of organic stereochemistry
Louis Pasteur
In 1848, Pasteur published a study on the recrystallization of various salts of_________, which are found naturally in wine (aka “________”).
tartaric acid, or “tartrates”
wine diamonds
An equal mixture of two enantiomers is called
racemic mixture or racemate
