Took a quiz.

Alkeynes

a+b c: Addition reaction

a B+C: elimination

a-b+c-d a-c+b-d substitution

a b rearrangement

"molecularity"

Drew graph of energy scale showing that a+b is higher energy than c.

• need to know what happens when you convert a+b into (mechanism) c
• Two different kinds of reactions

1. "concerted"
   • no intermediate products
2. stepwise
   • one or more high-energy intermediates (products)

Types of stepwise reactions (mechanisms)

1. heterolytic= (hererogenic=): electrons move 2 at a time (ionic interactions) {the majority of our reactions will be hererolytic}
2. homolytic=breaking (homogenic=forming): electrons pairs break 'apart' and you end up with free radicals (very few organic reactions do this)

• do not learn halogenation until after the first hour exam.

Gibbs Free Energy = G = H-TS

• H = enthalpy; bond strengths of all the bonds in a molecule.
• S = entropy; disorder in a system (floppiness, or number of conformations it can do)
• T= absolute temperature, Kelvin
• At low temperatures G~H
  • in organic chem this is usually true at room temperature.

• What drives these reactions is /\G = -RT ln Keq
  • eq = equilibrium
  • 
    

2A+B C

Keq= [C]/([A]²[B])

if /\G> 0 then Keq < 1

if /\G= 0 then Keq = 1

if /\G< 0 then Keq > 1