6. Organohalides Radical Halogenation Reactions Flashcards
what is a radical?
a atom with an unpaired electron
what type of arrow is used in radical reactions?
single-headed arrows
how do you predict where a radical reaction will transfer to?
the place where the radical is most stable
what are three things to consider when considering radical stability?
- hyperconjugation; whether the radical is tertiary, secondary or primary because the more substituted atom is more stable
- resonance, ability to move the radical
- hybridization; the less s character on the carbon, the more stable the radical is
how can you tell which carbon bond is weakest according to radical stability?
the more substituted it is
what is radical halogenation?
a reaction that allows halogens to be added to alkanes
What do radical halogenation reactions need to be performed and why?
they need a high temperature or light to initiate radical formation
what is shown above and below the arrow of radical halogenation reactions?
two of one halogen above the arrow and heat below the arrow
what are the three steps for radical reactions?
- initiation; a bond between two atoms turns into a radical on each atom
- propagation: the radical atom substitutes the bonded atom to become bonded
- termination; two atoms with radicals bonds together to get rid of their radicals
describe the general reaction of hydrohalogenation reactions with peroxide.
a molecule with a double bond has a halogen bond where the double bond is to reduce the double bond
how can you tell what the major product would be regarding hydrohalogenation reactions?
the major molecule will be the molecule with the most substituted halogen
how are the halogens added to the double bond in hydrohalogenation reactions?
to the least substituted carbon in the double bond using anti-Markovnikov
what molecules are used above and below the arrow of a hydrohalogenation reaction with peroxide?
hydrogen bonded to a halogen above the arrow and ROOR below the arrow
