ORGO I Alkenes and Stereoisomerism

IUPAC Naming, Common Naming, R and S Configuration, Chair Conformation...

dihedral angle

the angle between two bonds on adjacent carbons when viewed along carbon-carbon bond axis in a Newman projection

anti conformation

a staggered conformation with a 180 degree dihedral angle between the two largest groups; lowest in energy

gauche conformation

a staggered confirmation with a 60 degree dihedral angle between two non-hydrogen groups; exhibits gauche steric strain

eclipsed conformation

a conformation with a 0 degree dihedral angle where bonds directly line up; highest in energy

torsional strain

resistance to rotation caused by electron repulsion between eclipsed bonds

steric strain

interference that occurs when atoms or bulky groups are forced too close to each other in space

axial position

bonds on a cyclohexane ring that point straight up or straight down

equatorial position

bonds on a cyclohexane ring that point outward along the equator of the ringing flipr

ring flip

a conformational change interconverting chair forms where all axial positions become equatorial positions become axial

1,3 diaxial interaction

a type of steric strain caused by repulsion between an axial substituent on C1 and axial hydrogens on C3 and C5

cis cyclohexane

two substituents attached to the same face of a ring, both up or down

trans cycloalkanes

two substituents attached to opposite faces of a ring

constitutional isomers

compounds with the same molecular formula but different bond connectivitytereoisoms

stereoisomers

compounds with the same molecular formula and the same connectivity, but different 3D arrangements of atoms in spacentaniome

enantiomer

non-superimposable mirror-image stereoisomers. All stereocenters are inverted

diastereomers

non-superimposable, non mirror image stereoisomers

chiral center

a molecule that is connected to four different groups and lacks an internal plane of symmetry

achiral center

a molecule that has a plane of symetry and at least one identical group

meso compound

molecule containing two or more stereo centers that is achiral

stereocenter

a sp³ hybridized carbon atom bonded to four completely different groups conr

r configuration

clockwise direction when tracing priorities with priority 4 facing away

s configuration

counterclockwise direction when tracing points with priority 4 facing away (on a dash)

Fischer projection rules

2D representation where horizontal bonds project toward you and vertical bonds project away. if priority 4 is horizontal, reverse the apparent result