Organic Chemistry

When finding hybridization always remember about what

resonance structures which determine hybridization

sp hybridization has what geometry and bond angle

linear and 180

sp2 hybridization has what geometry and bond angle

trigonal planar, 120

sp3 hybridization has what geometry and bond angle

tetrahedral, 109.5

Oxygen exists normally with how many bonds and lone pairs

2 bonds and 2 lone pair

Nitrogen exists normally with how many bonds and lone pairs

3 bonds and 1 lone pair

Phosphorous exists normally with how many bonds and lone pairs

3 bonds and 1 lone pair

Sulfur exists normally with how many bonds and lone pairs

2 bonds and 2 lone pairs

MEMORIZE

What are Lewis Acids

compounds that serve as electron acceptors

What are Lewis Base

compounds that serve as electron donors

What is Bronsted Lowry Base

are proton (H) acceptors

What is Bronsted Lowry Acid

proton (H) donors

The lower the pKa, the _acid

stronger

What are the 7 strong acids

HBr,

HCl,

HI,

HNO3,

HClO3,

HClO4,

H2SO4

High Ka means

high Ka means strong acid. High Ka means lower pKa value

High pKa means

low Ka value. Also means weakest acid

What happens to acidity as we go down a column in the periodic table

Acidity increases because atomic size increases

In an acid-based reaction, what kind of acid is favored for production?

the formation of a weaker acid is favored

For an amino acid, what happens to the amino and carboxyl group depending on how high or low pH is

If the pH is higher than functional group’s pKa, then carboxyl group will be in base form (COO-) no Hydrogen. If pH is lower than pKa, carboxyl group will gain proton COOH. If pH is greater than pKa, amino group will be the same (NH2). If pH is less than pKa, amino group will gain proton NH3+

If atoms like Fluorine group are closer to carboxylic acid what does this mean in terms of how strong the molecule is

Groups like Fluorine when close to carboxylic acid, are electron withdrawing groups so they will stabilize the negative charge of the conjugate base of the chosen molecule, resulting in stronger acid.

Which ones are stronger acid one with carboxylic acid or only alcohol group

Carboxylic acid because the conjugate base of carboxylic acids are MORE STABLE

A bigger atom does what to acidity

increases acidity

Electron withdrawing groups like F, Cl, Br, I do what to acidity

increase

What are some electron withdrawing groups resulting in increasing acidity

From Greatest to smallest:

nitro (NO₂), (SO₃H), cyano (CN), carbonyls (CHO, C=O, COOH, COOR), halogens,

When determining which molecule is the most acidic: Use CARDIO after you convert each molecule into its conjugate base

C → Charge. Carboxylic acid is strongest acid. the more + charged molecules are the more acidic

A → Atom size. the bigger the size of atom the more acidic be. The more electronegative the atom is, the more acidic the conjugate acid is

R → Resonance! must be able to be resonance stabilized or do resonance (SO no cyclic rings without double bonds inside)

DI → Dipole induction. Which groups are the most electron withdrawing? As shown here

O → look at orbitals. sp most acidic > then sp2 > sp3 is least acidic

Strong conjugate base means..

weak acid (low Ka, high pKa)

weak conjugate base means

strong acid (High Ka, low pKa)

strong conjugate acid means…

weak base

weak conjugate acid means

strong base

What makes a molecule more basic in terms of what kind of functional group must be there and characteristics?

electron donating groups like

NH_2,

NH-R,

N,

OH,

O-R are strongest

then NHCO-,

OCO-,

lastly weakest is CH3, CH2CH3

Hydrogen bonding can happen intermolecularly between what kinds of molecules? Fundamental atoms in there that can allow this

Hydrogen (H) bonded to Nitrogen (N), Oxygen (O), or Fluorine (F).

Alkyne

triple bond. when naming for IUPAC want to assign this lowest number as possible. Numbering should go through it

-yne

Alkene

double bond. Try to assign lowest number. Counting should go through this.

-ene

Name this

Bicyclo[1.1.0]butane

butane is parent name because there is 4 carbons

bicyclo in front of name

name this

spiro[3.4]octane 

count all the carbons around the shape

establish parent name.

then count how many carbons are on opposite side of the vertices that both share.

label in brackets from lowest value to highest for spiro ones!!!

dont forget to put spiro in front

Name this

Bicyclo[3.2.1]octane 

first name it bicyclo

then count how many total carbons and establish parent compound

then count how many carbons are NOT shared on either side separated by the bridge

then count how many carbons are shared in the bridge

label from descending value highest to lowest

name this

1-methylbicyclo[4.4.0]decane

How do you name a molecule with functional group like this

We use “N,N-dimethyl” to indicate that there are two methyl groups bonded to the amide nitrogen.

Where should you place carbon 1 on this molecule

On the carbonyl.

what functional group has the highest priority when the parent name ends in “-oic acid”

carboxylic acid

ester

H NMR how to know if the signal will be singlet, doublet, triplet, quartet

n + 1 rule where n is the # of neighboring H’s around the designated proton and final answer will see if it is either one of those. The neighboring H must be from outside the carbon atom orignally attached to

Which compound will produce a large broad peak at 3200-3500 cm^-1 on IR spectrum

Alcohol group (-OH)

On an IR spectrum what are the characteristics of an Amine group (NH)

There will be a sharp peak at 3200-3500 cm-1 and a 2ndary amine (-NR2H) peak and two 1’ amine peaks (-NRH2)

On an IR spectrum what are the characteristics of an Carboxylic acid group (-COOH)

2500-3500 cm-1 and has broad jagged peak

On an IR spectrum what are the characteristics of an Nitrile group (C≡N)

2200-2250 cm^-1 and medium peak

On an IR spectrum what are the characteristics of an carbonyl group (C=O)

1700-1750 cm^-1 large sharp peak

On an IR spectrum what are the characteristics of an aromatic group

1450-1600 cm^-1 medium peak

Ethanol

Ethanal

Ester

the more bonds you make to an atom

it becomes + charge

s orbital what is the s character and p character percentage

100% s character and 0% p character

sp orbital what is the s character and p character percentage

s character 50% and p character is 50%

sp2 orbital what is the s character and p character percentage

s character → 33%

p character → 66%

sp3 orbital what is the s character and p character percentage

s character → 25% and p character is 75%

what does the double bond do in terms of rotation of certain groups in molecule

restricts rotation around the bond

Amine

IUPAC ester naming

separate the acidic and alcoholic side

acidic side (other side of the ester group) ends in -oate

alcoholic side (carbon attached to O of the ester) is named 1st and ends in -yl

→ ethyl 2-methylbutanoate

Benzene parent name IUPAC ranking

-COOH > -CN > COH > OH > NH₂ > CH₃

benzoic acid > benzonitrile > benzaldehyde > phenol > aniline > toulene

highest priority to lowest

amide

undecane

11 carbons

dodecane

12 carbons

name this compound

spiro [5.5] undecane

count total carbons of entire molecule without counting same carbon twice

Then, list the number of carbons on each side that ISNT shared from lowest to highest inside brackets, separated by a period. In this case, both sides have five carbons, resulting in [5.5].

name this compound

bicyclo [3.2.1] octane

list the number of carbons in each bridge in descending order inside brackets, separated by periods. In this case, one bridge has three carbon atoms, another has two, and the third has one, resulting in [3.2.1].

Constitutional isomers

molecules that share the exact same molecular formula but differ in how their atoms are connected.

Diastereomer

that have the same molecular formula and atomic connectivity.

However, they are non-superimposable and are not mirror images of one another.

R/S stereocenter determine

Find carbon with four unique groups

prioritize each group 1→ most priority

following the 1… if

cw, R

if ccw, S

how to find total number of stereoisomers

2n where n→ # of stereocenters

Enantiomer

nonsuperimposable (cannot be stacked on top identically) mirror images of one another. 🪞🪞

A pair of enantiomers exhibits opposite R/S configurations at each chiral center.

• same physical properties, such as

• boiling point,

• melting point,

• solubility,

• and density.

• They rotate plane-polarized light 💡🔦by the same amount in opposite directions. 

Which is more thermodynamically stable E or Z

E

Are chiral compounds optically inactive or active

optically active and can rotate plane-polarized light

Are Meso compounds optically active

optically inactive because of plane of symmetry

Are achiral compounds optically active

No they are inactive

How to know if a compound is chiral or achiral

Chiral → at least one stereocenter: carbon bonded to 4 unique substituents and lacks internal plane of symmetry

Achiral → lack a stereocenter and contains internal plane of symmetry

internal plane of symmetry is a vertical line down the middle

Asymmetric carbon meaning

also called stereocenter where a carbon is bonded to 4 unique substituents

When finding R/S use the Cahn-Ingold Prelog system what are the general rules

1. identify stereocenter

2. prioritize 4 substituents

3. number them 1-4 based on priority

4. point the lowest priority group 3D AWAY from you

5. draw a circle from 1-4

6. CW → R
   CCW → S

Cabonyl group C=O IR spectrum

big pointy peak at 1700 + or - 50 cm

C=C or C=N IR spectrum

Small to medium peak at 1600-1700 cm^-1

OH alcohol group IR spectrum

A LARGE, broad trough far to the left for alcohols and on top of 3000 cm^-1

C-H IR spectrum

Big, pointy peaks coming straight down around 3000 cm^-1

N-H IR spectrum

A sharp peak to the left of 3000 cm^-1 (around 3200-3500 cm^-1)

(one peak for –NH, two peaks for –NH₂)

C≡N (a nitrile) IR spectrum

Medium-sized peak at ~2200 cm^-1

NO₂ (nitro) IR spectrum

Vampire teeth 🦷🧛‍♀ at 1500-1600 cm-1 and 1300-1400 cm-1

degree of unsaturation

it is calculated by adding the number of pi bonds and the number of rings together:

Also calculated with this formula

where C represents the number of carbon atoms, H represents the number of hydrogen atoms, X represents the number of halogen atoms, and N represents the number of nitrogen atoms:

UV spectroscopy

laboratory technique used to analyze compounds with conjugated alkenes.

Conjugated alkenes have alternating double and single bonds

What element when on a mass spectrometry shows distinct M and M+2 patterns with equal abundance

Bromine (Br)

• naturally occurring isotope

• has 2 isotopes where both produce peaks of M and M+2

What element when on a mass spectrometry shows 9:6:1 ratio of M, M+2, and M+4 peaks.

presence of 2 Chlorine atoms Cl₂

determining the number of ¹³C-NMR signals

count the number of distinct carbon atoms, as each unique carbon environment produces a separate peak in the spectrum.

remember planes of symmetry

¹³C-NMR spectroscopy chemical shifts downfield (left) at what ppm values

higher ppm

¹³C-NMR spectroscopy chemical shifts up field (right) at what ppm values

lower ppm values

¹³C-NMR spectroscopy

Carbonyl (C=O) carbons

• Esters, amides, and carboxylic acids

• Aldehydes and ketones whats the chemical shift in ppm

160-180 ppm
> 200 ppm

H -NMR spectroscopy rules

the N + 1 rule, where N represents the number of neighboring hydrogens.

When no hydrogens are present on adjacent atoms, the signal appears as a singlet (n= 0 so 0 + 1 = 1)

doublet → one hydrogen is present on adjacent atoms N= 1 so 1 + 1 = 2 doublet

triplet → where 2 hydrogens next to primary hydrogen N = 2 2+1 = triplet 3

¹³C-NMR spectroscopy reading peaks. If there is a peak around down left with higher ppm numbers, what ppm is this and what group

higher ppm numbers, deshielded, more + charged

Aldehydes and ketones C-O-H or C=O >200 ppm