Orgo 2-Aromatic Compounds Ch 17

Nomenclature of Aromatic Compounds

1) parent chain

2) functional groups

3) substituents(branching)

4) numerical location

you can use ortho/para/meta instead of numbers

toluene

phenol

anisole

aniline

benzoic acid

benzaldehyde

acetophenone

styrene

xylene

benzyl

ortho

1,2

meta

1,3

para

1,4

what’s the name for this?

what’s the best name for this?

d

Huckles rule

determines aromatic, anti, or non aromatic (4n+2=2,6,10)

Frost circles

1) draw a polygon with one corner facing downwards

2) draw MO’s on all corners

3) Draw line that splits in the middle

4) above the line is antibonding, below is bonding, on line is non-bonding

Requirements for aromaticity

1)cyclic

2) fully conjugated (pi bond skips sides)

3) planar (6 elements or less)

4) Huckles rule (4n+2=even number)

failure of aromaticty test (doesn’t meet 1 or more of the crieteria)

non aromatic

Meets all aromaticity conditions but only has 4n pi electrons

anti aromatic

what’s the stability flow?

aromatic>non-aromatic>anti-aromatic

which one is aromatic

a

(1) oxidation reagents 1(must have 1 hydrogen at the benzylic position)

Jones reagent (Na2Cr2O7) and H2SO4,H2

(1) oxidation reagents 2 (must have 1 hydrogen at the benzylic position)

KMnO4/H2O,Heat……..H3O+(quenching)

(2) Free Radical bromination reagents

NBS/Heat

(3) Substitution Reaction reagents 1

H3O/(sn2)

(3) Substitution Reaction reagents 2

NaOH/(sn2)

(3) Elimination rxn reagents 1

conc H2SO4/ (e1)

(3) Elimination rxn reagents 2

NaOEt/(e2) 

Reduction (Hydrogenation 1) reagents

3H2, Ni/100atm 150C

Reduction (Hydrogenation 2) reagents

H2, Pt/ 2atm 25C

Birch reduction

Na, CH3OH/NH3

(carbons attached to alkyl groups won’t be reduced only when attached to electron-withdrawing groups.) 

SN2 rxns

strong nu, unsubstituted, backside attack

SN1 reactions

neutral nu, highly substituted

E2 rxn

strong nu, highly subst, regioselective, stereospecific

E1 rxn

weak nu, highly substi, no anti-coplanar