Organic Chemistry

Same molecular formula, but different structures.

• Structural (Constitutional) Isomers: differ in connectivity (only share molecular formula)
• Steroisomers: have the same connectivity

Same molecules but differ in the rotation around a single bond.

• Newman Projection
• Staggered: when the molecules don't line up in a Newman Projection
• Anti Staggered: two largest molecules are antiparrallel
• Gauche: two largest molecules are 60 degrees apart
• Eclpised: when there is overlap of substituents and two largest groups are 120 degrees apart
• Totally Eclipsed: direct overlap of largest substituents

• Angle Strain: results when bond angles deviate from ideal behavior (cyclohexane most ideal)
• Torsional Strain: strain when ring has to undergo eclipsed or gauche interactions
• Nonbonded Strain (Van Der Waals Repulsion): steric strain

Can be chair, boat, or twist-boat cyclohexane. It can also undergo a chair flip with chair conformers. The most stable conformer is when the largest substituents are equitorial. Can be cis or trans, but you have to look at no chair version of it.

• Equitorial: off to the sides
• Axial: up an down

• Chiral: has a nosuperimposable mirror image. They are also optically active.
• Achiral: superimposable mirror

• Diastereomers: chiral and share same connectivity but NOT mirror images. They have different chemical and physical properties.
• Enantioners: mirror images of each other. They have similar chemical and physical properties  but polarize light differently. (d- is + ; l- is -)

Standard rotation for chiral enantiomers.

(specific rotation) = (observed rotation in degrees)/(concentration * path length)

Configuration: spacial arrangement of atoms.

• Relative Configuration: configuration in relation to another chiral molecule
• Absolute Configuration: exact spacial arrangement of atoms independent of other molecules

It is based on atomic number, not the group as a whole. You must also go Carbon to Carbon deciding highest priority.

• E: epposite sides
• Z: zame sides

• Have the thumb face the hydrogen.
• R: right hand spin
• S: left hand spin

When assigning priority, H is always 4

X-axis are wedges, Y-axis are dashed lines

To bring the lowest away from you, turn the molecule 180 degrees (NOT 90 degrees) or swap x-axis 1 with y-axis 1 and x-axis 2 with y-axis 2

Ability of a molecule to rotate plane-polarized light.

• d- or (+) rotate light to the right
• l- or (-) rotate light to the left

Contains equal concentrations of enantioners. They also cancel each other out making the mixture NOT optically active.

• 2ⁿ
• n = stereocenters

• Lewis Acid: electron acceptor (electrophile with a positive polarization)
• Lewis Base: electron donor (nucleophile with a negative polarization)
• Bronsted-Lowry Acid: proton donor
• Bronsted-Lowry Base proton acceptor

A molecule that can act as an acid or a base.

• H₂O
• Al(OH)₃
• HCO₃^-
• HSO₄^-

Measure of the strength of the acid. Higher the K_a value, stronger the acid.

Ka = [H⁺][A^-]/[HA]

• pK_a = -logK_a
• -2 and lower: strong acid
• -2 to 20: weak acid
• 20 and higher: strong base

Bond strength decreases going down a periodic table. This means that there is a higher chance of an acid donating a proton, such that acidity increases.

The more electronegative the atom, the more electrophilic it is, the more acidic it is.

~50

~43

42

~35

25

25 (R-COOR)

20-24

17

16

4

-1.7

• Most Carboxylic Acid Derivatives
• Alcohols
• Aldehydes
• Carboxylic Acids
• Ketones

Amides and Amines

Nucleus loving molecules that make good bases. Nucleophile strength is based on kinetics, NOT thermodynamics.

• Polar Protic: can hydrogen bond; nucleophilicity increase ↓ a period (the weaker nucleophile would want to form more bonds with the protons in the solution causing it to not access the electrophile)
• Polar Aprotic: cannot hydrogen bond; nucleophilicity increase ↑ a period (no protons attacking nucleophile so they are free to attack electrophile)

• Protic: can hydrogen bond (polar)
• -carboxylic acids
• -ammonia
• -amines
• -water
• -alcohol

• Aprotic: cannot hydrogen bond (nonpolar)
• -DMF
• -DMSO
• -acetone

• 1) the more (-) charged nucleophile is best
• 2) the less electronegative nucleophile is best
• 3) less substituted nucleophile best
• 4) if the solvent is aprotic, it increases strength of nucleophile (it doesn't provide protons that deter effects of nucleophiles)

• HO^-
• RO^-
• N₃^-
• CN^-

• NH₃
• RCO₂^-

• H₂O
• ROH
• RCOOH

• -stronger acid
• -higher (+) charge
• -more electronegative
• -better leaving group

They are the molecules that take all the electrons during a heterolytic reaction (a reaction where bonds break, and all electrons from that bond move towards one atom).

The best leaving groups are weak bases (conjugate bases of strong acids). Strong bases are too nucleophile's to want to leave the molecule. They are also molecules capable of resonance for stabilization.

A reaction in which a necleophile attacks a molecule, causing a leaving group to leave. The attacking nucleophile must be a stronger base than the leaving group.

• Unimolecular Nucleophilic Substitution Reaction
• Two step reaction:
• 1) leaving group leaves forming a carbocation
• 2) nucleophile attacks

• Rate determining step: the formation of the carbocation is the rate determining step. This means that the rate depends on substrate concentration.
• rate = k[R-L]

Primary product formed: racemic mixture produced because nucleophile can attack either side.

Configuration of attacked molecule prefer-ability: the more substituted the carbocation, the more stable it is, the more favored S_N1 is

• Bimolecular Nucleophilic Substitution Reaction
• Single step reaction.
• 1) the nucleophile conducts a back sided attack

• Rate determining step: since it only has one step, the rate falls on the entire reaction. This also means that the rate depends on both substrate, and nucleophile.
• rate = k[R-L][nuc]

Primary product formed: since it is a back side attack, the product has an inverted configuration if the attacking group has the same bond order

Configuration of attacked molecule prefer-ability: S_N2 reactions prefer molecules that are less substituted. This is because substitued reaction only produces more steric hindrance.

Turning a primary and secondary alcohol into an aldehyde or ketone.

(Good Oxidizing Agent)

Turning a primary and secondary alcohol into an aldehyde or ketone.

(Good Oxidizing Agent)

Turning an aldehydye or an alcohol into a carboxylic acid.

(Good Oxidizing Agent)

Turning an aldehyde, alcohol, and a benzene with a methane attached into a carboxylic acid.

(Good Oxidizing Agent)

Turning an aldehyde into a carboxylic acid.

(Good Oxidizing Agent)

Turning an alkene with one carbon having one substituent and the other having two, into a ketone and a carboxylic acid.

Turning an alkyne into two carboxylic acids.

(Good Oxidizing Agent)

Turning an alkene into two ketones.

(Good Oxidizing Agent)

Turning an alkene into two ketones.

(Good Oxidizing Agent)

Turning an alkene with one carbon having one substituent and the other having two, into a ketone and a carboxylic acid.

Turning an alkyne into two carboxylic acids.

(Good Oxidizing Agent)

Turning an alkene into OH groups on both sides (cis)

(Good Oxidizing Agent)

Turning an alkene into OH groups on both sides (cis)

(Good Oxidizing Agent)

Turning an alkene into an epoxide

Turning a ketone into an ester

(Good Oxidizing Agent)

Diol (2 cis alcohol groups on adjacent carbons) splits in two forming an aldehyde

(Good Oxidizing Agent)

Diol (2 cis alcohol groups on adjacent carbons) splits in two forming an aldehyde

(Good Oxidizing Agent)

Diol (2 cis alcohol groups on adjacent carbons) splits in two forming an aldehyde

(Good Oxidizing Agent)

Turning an aldehyde or a ketone into a primary or secondary alcohol.

(Good Reducing Agent)

Turning an amide (like a carboxylic acid except the single bonded O group is N) into a primary amine (No O groups)

(Good Reducing Agent)

Turning a carboxylic acid into a primary alcohol.

Turning an ester (O=C-O-R) into two primary alcohols.

(Good Reducing Agent)

They have low electronegativities and low ionization energies.

• H-
• Sodium
• Aluminum
• Zinc
• Hydrides like NaH, CaH₂, LiAlH₄, NaBH₄

High oxidation state and bigger love for electrons.

• O₂
• O₃
• Cl₂
• MnO₄^-
• CrO₄^2-
• CrO₇^2-
• PCC

It is the carbon with the most highest electronegative groups attached to it.

It has a higher chance of reacting with the highest priority functional group because it contains the most oxidized carbon.

So it is more likely to react with a carboxylic acid, than an alcohol.

You can add in a diethanol and H+ to the molecule. It causes the carbon attached to the ketone to bond to lose the alcohol and attach to both alcohols (now ethers).

Acts as a protecing group.

• 1) Carbonyl carbon because it is very electrophilic
• 2) α-H attached to the adjacent carbonyl carbon because it is very acidic due to resonance

A more conjugated carbon is much more stable. This means that in a reaction, an organic compound is less likely to form something that is less conjugated because it is less stable.