chapters 5-6-7 Flashcards
constitutional isomers
same molecular formula but different structural formula
stereoisomers
differ in 3d arrangement of atoms
conformation
different versions of a molecule assuming that free rotation is paused
torsional strain
strain caused by groups eclipsing and wanting to twist away from each other
steric stain
strain caused by the repulsion of groups in close proximity
angle strain
strain caused by angles that are reduced
what are the strains in cyclopropanes
- lots of angle strain because their bond angles are of 60 instead of 109.5
-all of their hydrogens are eclipsed so torsional strain
what are the strains in cyclobutanes
-torsional strain if it is flat because all h will be eclipsed but less torsional strain if 2 c up and 2 c down because they will all be staggered
-steric strain due to axial positions
-lots of angle strain since angles are of 90 instead 109.5
what makes for a chiral molecules
-at least one chiral c (Sp3 Carbon with all different groups)
-no plane of symmetry
-# of possible stereoisomers = 2^n where n is the # of chiral C
what is the opposite of chiral
achiral
what is a miso compound
a molecule that is superimposable with its mirror image
what is a racemic mixture
an equal amount of both enantiomers
what does a junction in a fisher projection represent
a chiral carbon
what does a vertical line represent In a fisher projection
substituents going into the plane
what does a horizontal line represent in a fisher projection
a substituent coming out of the plane
clockwise
R
counterclockwise
S
1R and 1S (1 chiral center)
enantiomers
1R and 1R (1 chiral center)
same molecule
2R and 2S (2 chiral centers)
enantiomers
4R (2 chiral centers)
same molecule
3R 1S (2 chiral centers)
diastereoisomers
what is an addition reaction
a reaction that has a double or a triple bond of some sort and is added a group to one of the c that makes this bond
what is an elimination reaction
a reaction where a molecule is taken 2 groups to from a ∏ bond