Question

5. Resonance provides the basis for a large portion of organic chemistry and helps us identify sites of high and low electron density. We will see that the electron source (nucleophile) is attracted to the site of electron sinks or deficiency (electrophile). For the following, draw the curved arrow that shows the movement of electrons that takes you from one resonance structure to the other. Remember to always start your arrow at the source of electrons (r-bond or lone pair). Next to the resonance structures draw the resonance hybrid and assign partial charges: Rule reminders for drawing resonance structures: a. Do NOT break sigma bonds. b. DO NOT break the octet rule. Be careful of line structure! Draw in all around an atom that experiences change so that you do not accidentally give a C, N, or o more than 8 electrons. DO NOT give an electronegative element such as O, N, F fewer than 8 electrons. d. Do move lone pairs or pi electrons towards a positive charge or pi bond. e. Do move pi electrons towards the more electronegative atom, if applicable. Take it slow - when asked to draw "all possible resonance structures” start by drawing the minimum number of arrows possible while not breaking the octet rule. Draw the resulting structure then ask yourself if there are any other possibilities. g. Check each resonance structure carefully to be sure you have not broken rules 1-3 above. f. Take O-0

Answer 1

This is more stable resonance Sinu elu- me due to the elect negative changed placed in mone electronegative N-atom. LOTY - BY ET This is the mone stable resonating struchu- ne because it consist a anomalie system which have extra stabilization enengg 1 S O- This mesonating struct- une is much more. effective due to the mone ts value of canbo- nyl carbon of aldehyde. Alco NetNO NCENT This is more stable due to the negative changed Placed in more electro- negative atom. HH 5:2-I H It is mone stable I because + change transfer mone electro negative atom (o) to less electronegative atom (N)

O 6:2 - I It is more stable because it is not a changed species. Neutral compour na is much more stable.