FUNCHEM 22 - Introduction to Organic Chemistry II Flashcards
What is the length and bond angle of a single, double, and triple bond?
single: 110 pm & 109.5 degrees
double: 133 pm & 121.7 degrees
triple: 120 pm & 180 degrees
Define structural isomer.
Structural isomers are two molecules that have the same molecular formula, but different atom connectivity. Therefore, they have different physical and chemical properties.
Define geometric isomer.
Geometric isomers have the same atom connectivity, but a different arrangement of atoms in space due to the lack of free rotation around a double bond. Cis means the bonds are on the same side & trans means they are on opposite sides.
Define chiral molecule.
A chiral molecule is a carbon atom with four different groups attached to it (stereogenic center) as is gives rise to two stereoisomers. Chiral molecules:
- do not have a PLANE OF SYMMETRY, meaning no two or more substituents on the carbon are the same.
- are enantiomers which are chemically identical, but have different biological properties that are very important for drug-enzyme/receptor interactions.
Define achiral molecule.
An achiral molecule is any molecule that has a plane of symmetry, meaning two or more substituents on the carbon are the same.
Define enantiomers.
A pair of molecules that are non-superimposable mirror images of each other.
What is a hydrogen bond and where does it occur?
It is the interaction between a hydrogen atom and a very electronegative atom (H, O, F). Hydrogen bonding can occur between molecules in water, alcohols, and amines increasing their melting and boiling points, as some molecules can become hydrogen bond donors and others can become hydrogen bond acceptors. The amide bond formed in protein structures is a result of hydrogen bonding, the bonds formed between purines and pyrimidines are the result of hydrogen bonding, and dopamine and morphine contain hydrogen bonds as well.
