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dicarboxylic acid names
Oh my such a good apple pie → oxalix, malonic, succinic, glutaric, adipic, pimelic
differences between 13C and H NMR (3)
1. 13C is 0-200 δ, H is 0-10 δ; 2. need larger sample for 13C since only 1.1% of all C are 13C; 3. coupling between C atoms is not observed in 13C because so few C atoms are 13C
disproportionation
radical (formed during pyrolysis) transfers a hydrogen atom to another radical, producing alkane and alkene
distillation
used to separate two miscible fluids (that can't go through extraction) with different bps
distillation types (3)
simple (both bps below 150° and at least 25° apart), vacuum (bp above 150° and at least 25° apart - vacuum lowers bp and thus prevents decomposition due to excessive temp), fractional (bps less than 25° apart, uses fractional column with condensing beads to repeat distill liquid)
double and triple bonds in molecule naming
y-root-en-x-yne; y is number of double bond and x number of triple, root is prefix for main carbon chain; double bond given lowest number when there is a choice; x + y is as small as possible
E/Z
E opposite, Z same
E1 over SN1
high temp, highly hindered base (bad nucleophile)
E2 over SN2
sterically hindered electrophiles (form stable alkenes but too hindered for SN1), strong base (SN1 favored by weak Lewis bases that are strong nucleophiles)
E2 vs. E1
E2 uses strong bases, E1 weak bases
electron donating, withdrawing, and resonance effects on acidity
electron withdrawing and resonance stabilize conj. base and thus increase acidity; electron donating destablizes conj. base and thus decrease acidity
eluant
solvent in TLC
elute
mobile phase elutes (displaces) substances adhered to stationary phase in chromatography
enamines
nitrogen analogs of enols (amine group attached to one carbon of C=C
enatiomers
non-superimposable mirror image molecules, have identical physical and (mostly) identical chemical properties
epimers
differ in configuration of one carbon
ether IR absorption
1100 cm^-1
extraction
transfer of dissolved product from one solvent into another in which it is more soluble, leaving impurities behind in first solvent (using aqueous and organic layers)
extraction of acids
adding a base helps extract the acid's anion (result of acid dissociation) to the aqueous layer
fingerprint region
400-1500 cm^-1 region of IR spectrum specific for each molecule
Fisher projection
horizontal out of page, vertical into page (man with bowtie)
flash column chromatography
solvent forced down column with nitrogen gas
for any molecule with n chiral centers, how many possible steroisomers?
2^n
free-radical HX addition vs. normal addition
free-radical (HBr + peroxide) violates Markovnikov → H adds to most subsituted (since -Br adds first) → free radical doesn't work for HCl or HI
Gabriel synthesis
converts primary alkyl halide to primary amine with phtalimide, KOH, and ethanol; no polysubstitution possible like with ammonia + RX
geminal
diols with hydroxyl groups on same carbon
geometric isomers
differ in position of substituents around double bond; differ in all physical properties and many chemical ones
glycogen
1,4 α glucose with 1,6 α branching
glycol
diol
glycoside
acetal sugar (non-reducing)
glycoside formation
hemiacetal or hemiketal + ROH/H+
GR + ester
1 eq. produces ketone (-OR leaves, R' enters), ketone is more reactive so second eq. produces tertiary alcohol (R'2ROH)
H2/cat and 100°C with benzene rxn
cyclohexane
Henderson-Hasselbalch equation
pH = pKa + log ([conj. base]/[conj. acid])
Hg(CH3COO)2 reacts
mercuric acetate, used to add water to double bonds (direct addition has problems with yield variation)
Hofmann elimination
exhaustive methylation of amine with MeI→ quaternary ammonium iodide + Ag2O/H2O → 4nd ammonium hydroxide + heat → least subst. alkene and amine through elimination
Hofmann rearrangement
converts amides to primary amines with loss of the carbonyl carbon → use BrO-, go through rearrangement to isocyanate (OCNR), products
hot, basic KMnO4 reacts
alkenes or alkynes cleaved to form two carboxylic acids (if terminal, one carb. acid and CO2)
Huckel's rule
aromatic compounds have 4n + 2 π electrons, anti-aromatic have 4n
hydrates
geminal diols
hydrogen bonds form with what atoms
F, O, N → "phone"
imines
N=C (nitrogen analogue of carbonyl)
ion exchange chromatography
beads in column coated with charged substances to bind cations or anions
IR absorption of =CH
3100 cm^-1
IR vibration types
stretching (1500-4000 cm^-1, largest change in energy), bending (400-1500 cm^-1), rotation
isobutyl
.-CH2CH(CH3)2
isobutylene
CH2=C(CH3)2
isocyanate
RNCO
Jone's reagant
CrO3/H2SO4/acetone → oxidizes alcohols to ketones or CA
LAH vs. NaBH4
LAH more powerful (reduces carboxylic acids and esters), NaBH4 more selective (won't reduce CA and esters)
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