ACS CHEM FINAL

For Hawthorn projections, how do you differ wedges and hashes on hexane drawings?

wedges = up and Dashes = Down.

For molecular orbitals, how would you draw all the arrows?

You have to draw them in opposing directions, first you put all arrows UP, then you draw them DOWN, but make you make sure the lower orbitals are fi

Write out the hubridization for all bonds?

Triple bonds = sp

Double bonds = sp2

Single bonds = sp3

How is radical stability ranked?

primary (least stable) < secondary < tertiary (most)

Resonance does not ___________.

change the atoms!!! an O is an O

• Lowest to highest boiling points:

• Just alkane groups < OH < CA acid 

What is most soluable in water 

propanol

Amide vs amine

Define Hydrogen Bonding

A special, stronger type of dipole-dipole interaction that occurs when hydrogen is covalently bonded to a highly electronegative atom — specifically fluorine (F), oxygen (O), or nitrogen (N) — and is attracted to another electronegative atom nearby.

What is an example of hydrogen bonding?

Water (H₂O) — hydrogen bonds form between the hydrogen atom of one molecule and the oxygen atom of another.

What is Dipole-Dipole Interactions?

Give an example of dipole-dipole ineraction

HCl — the partial positive hydrogen is attracted to the partial negative chlorine of a neighboring molecule.

S vs R steochemistry 

R (right - clockwise) and S (left - counterclockwise)

Rank the priority groups for S vs R stereochemistry

Higher atomic number = higher priority

(Iodine> Bromine > Clorine > Oxygen > Carbon > hydrogen) iodine has the highest atomic number (53) is the highest.

Rank the following priority groups for R and S:

I, H, CH3, CHO, NH2, OH, Cl, SH, Br

highest: I > Br > Cl > SH > OH > NH2 > COOH > CHO > CH3 > H (always lowest/lower)

For Newmann projections, the front carbon is represented by a _____________, and the back carbon is represented as a _________.

dot, and circle

What makes a compound optically active ?

The molecule must have at least one chiral center — a carbon atom bonded to four different groups.

E vs Z sterochemistry 

Z (together) = the higher priority groups on each double-bonded carbon are on the same side

E (opposite) = the higher-priority are on opposite sides

Constitutional isomers vs enantiomers vs conformational isomers vs diastereomers 

Constitutional isomers = same molecular formula, but atoms are connected differently

Conformational Isomers (conformers) = same molecules, but differ by rotation around single (sigma) bonds

Enantiomers = non-superimposable mirror images

Diastereomers = stereoisomers that are NOT mirror images

Bronsted acid =

H+ donor

Bronsted base =

proton acceptor

Lewis acid =

molecular capable of accepting a lone pair of electorns

Lewis base =

electron pair donor

Nucleophile

electron rich and capable of donating an electron pair

Electrophile

accepts an electron pair forming a bond

Weakest to strongest acid =

organize the following = H3C-OH,  H3C-NH2, H3C-NH3+, H3C-OH2+

 H3C-NH2 < H3C-OH < H3C-NH3+ < H3C-OH2+

Base strength based on hybridized orbitals:

• sp < sp2 < sp3 

K>1 vs. K < 1 for the reactants vs products thing

K>1 = the acid on the product side is stronger than the reactant

K<1 = the acid on the reactant side is stronger than the reactant

what does K =

K=[reactants] / [products]

Nucleophiles rated slowest to fastest:

rank the following, CH3O-, CH3OH, and CH3NH2

CH3OH < CH3NH2<CH3O-

What is the Alkyl halide expected to undergo an SN1 reaction most rapidly…

HI is the strongest conjugate acid to the halides

SN1 vs. SN2. How many steps is each?

SN1 = 2 steps: leaving group leaves first, forms carbocation, nucleophile then attacks carbocation to form the product.

SN2 = 1 step: nuc attacks electrophilic carbon (w/leaving group) simutaneously as the LG leaves

SN1 works best with ____________, and SN2 works best with _______________.

SN1 = tertiary carbocations

SN2 = Works best with methyl or primary carbons

For __________, the configuration does __________.

For SN2 reactions, the wedge will invert to the hash.

After doing Subsiution (ex: Br on a wedge is treated with NaI in acetone) = inversion of chemistry happens so the Br leaves and the I is now on a hash!! This is due to ____________.

The reaction being SN2. SN1 can have inversion, but its not garenteed.

E1 and E2 both ______________.

result in the formation of a double bond (alkene)

What are the differences between E1 and E2?

E1 = 2 steps = Leaving group leaves → forms a carbocation. (carbocation present).

E2 = 1 step = The base removes a β-hydrogen at the same time the leaving group leaves (no carbocation)

• What is the product of dehydrohalogenation by KOH?

typically an alkenee!!!!!!!!

Which Hydrogen i preferably abstracted by dehyrohalogenation with KOH?

Yes — the preferred hydrogen abstracted during dehydrohalogenation with KOH is the β-hydrogen.The most substituted (more stable) alkene is typically favored, so the β-hydrogen removed is usually the one that leads to the more substituted double bond.

What does H₂O / H⁺ do?

Markovnikov addition of –OH (OH to more substituted carbon).

What does BH₃/THF → H₂O₂/OH⁻ do?

• Hydroboration-oxidation of alkenes.

• Anti-Markovnikov addition of OH.

Hg(OAc)₂/H₂O → NaBH₄/OH⁻

Markovnikov hydration.

B₂H₆/H₂O₂, NaOH

Anti-Markovnikov addition of OH.

What does H₂O / H₂SO₄, HgSO₄ do?

• Markovnikov addition → forms ketone via enol intermediate.

HOEt, H⁺

–OH replaced with –OEt.

Reduction of triple bond but not double

• Li, EtNH2, -78 C followed by NH4Cl wash 

What does DIBAL do?

used to reduce carboxylic acids and derivatives to aldehydes

What does LiAlH4/THF followed by H+ do?

reduces ketones, carboxylic acids, and derivatives to alcohols

Primary OH can be oxidized to ______________.

aldehydes or carboxlyic acids

PCC does what

PCC oxidizes a primary OH to an aldehyde and a secondary OH to a ketone

NaBH4/EtOH followed by H+ does what

•  selectively reduces ketones to OH

CrO3/H2SO4pr chromic acid oxidizes a primary OH to ? and a second OH to a __________.

Primary = CA

secondary = ketone

KMnO4 and Primary OH to what?

carboxlyic acid

O₃ (ozone) + H₂O₂ or oxidative workup + alkene

carboxxlyic acids /ketones

O₃ + Zn / DMS (reductive workup) + alkene =

aldehyde/ketone

MCPBA + alkeene =

epoxide

OsO₄ / H₂O₂ + alkene =

vicinal diols (syn)

LiAlH₄ (LAH) reduces esters/CA acids =

primary OH

LiAlH₄ (LAH) reduces aldehydes=

primary OH

LiAlH₄ (LAH) reduces ketones =

secondary OH

LiAlH₄ (LAH) reduces amides to

amines

NaBH4 reduces aldehydes to =

primary OH

NaBH4 reduces ketones =

secondary OH

H₂ / Pd, Pt, or Ni does what?

reduces everything

H2/Lindlars reduces alkynes to ___.

alkenes

Na / NH₃ (liq) reduces alkynes to _______

alkenes

DIBAL reduces esters to _____

aldehydes