Flashcards in Alkenes Deck (16):
What are stereoisomers?
Compounds with the same structural formula but a different arrangement in space
What is E/Z isomerism?
Stereoisomerism in terms of restricted rotation around a C=C double bond
What special part is needed in the name of an alkene?
En or Ene
What is the name of the main bond and the secondary bond in a double bond?
Main bond = Sigma bond
Secondary bond = Pi bond
How does a pi bond form?
The sideways overlap of two P orbitals
Which bond is weaker, sigma or pi?
What do the CIP rules state about E/Z isomerism?
The group with a larger atomic mass on the end of a bond is the higher priority group.
What do E and Z mean in E/Z isomerism?
E = Entgegen = Apart = Opposite sides
Z = Zusammen = Together = Same sides
What are the four addition reactions of alkenes and what are their conditions?
1. Addition of Hydrogen - Nickel catalyst
2. Halogens (i.e Cl2) - RTP
3. Hydrogen Halide (e.g. HBr)
4. Addition of Water - Phosphoric acid catalyst
What is the mechanism of addition to alkenes and how is it shown?
1. Line from double bond to delta positive charge atom, and line from the molecule's bond to the delta negative atom
2. Line from the electron pair on the negative ion
3. Complete new product
What does electrophile mean?
Attracted to pairs of electrons
What does Markownikoff's rule state?
The non-hydrogen atom goes to the carbon with most carbons attached
How is atom economy calculated?
Mr of desired product
---------------------------------- x 100
Sum of Mr of all products
How is percentage yield calculated?
--------------------------- x 100
How does addition polymerisation work?
Multiple small monomers