UMaine Organic Chemistry Exam 2

meth

1 carbon

eth

2 carbon

prop

3 carbon

but

4 carbon

pent

5 carbon

hex

6 carbon

hept

7 carbon

oct

8 carbon

non

9 carbon

dec

10 carbon

undec

11 carbon

IUPAC Steps

1. Identify and number the parent chain

2. name branches

3. write in alphabetical order

-yl

suffix for brances

-ane

suffix for parent chain

cyclo-

in a ring

Parent chain must be…

All linear or all cyclic

Included with alphabetizing

parent chain, branches, Cyclo,

partial charges come from?

polar covalent bonds

degenerate orbitals

orbitals with the same energy

Higher energy =

Less stable chair conformation

boat confirmations

stearic (flagpole) interactions only happen in…

axial

up/down

equatorial

outward

equatorial/axial, up/down

__ changes in chair conformation swap but __ doesn’t

bigger, equatorial

the favored chair conformation is the one with the ___ group as ___ because it needs more space

Enantiamers

Swap all dashes/wedges

Diasteriamers

Swap only some dashes/wedges

Stereoisomers

Enantiomers and Diasteriomers

Cahn-Ingold pre-log system 

1,2,3 arrangement of chirality centers

R

clockwise

S

counterclockwise

2^n

Max # of stereoisomers

completely different

Different molecular formula 

constitutional isomers

Different connectiviy

identical

same molecular formula, same connectivity, same configuration of chirality centers

ℎ𝜈

Symbol for light (Energy)

Delta

symbol for heat (Energy)

Exothermic

Product E is lower than starting E (Energy released)

Endothermic

Product E is greater than starting E (Energy required)

Delta G

difference in E between starting and products

Ea (activation energy)

starting E to transition state E

Large Ea

= slower reaction

Catalyst or heating

ways to improve reaction rate

Adding a catalyst means…

lower Ea with alternative Rxn pathway

Heating the reaction means…

Same pathway, but molecules have more energy to get through that pathway

Concerted

single transition state, no intermediates (all bonds break at same time)

stepwise

multi transition states and intermediates

Substrate

Organic compound thats reacting

Reagent

Helping or reacting with the substrate

Mechanism

curved arrow e- flow

Rxn coordinate diagram

Energy vs Rxn progress

Nucleophiles

Have extra e- density

Electrophiles

lacking e- density

Primary carbocation

1 c and 2 h attachments (unstable)

secondary carbocation

2 c and 1 h (stable)

Tertiary carbocation

3 carbon attachments (very stable)

classifications of transition states in stepwise reactions

rearangement, nucleophilic attack, loss of leaving group, and proton transfers