CHEM 215 FINAL

Conjugated dienes

cis: same side

trans: opposite sides (more stable)

spirobicycles

2 rings connected by a single atom

Fused bicycles

2 rings that share 2 atoms

bridged bicycles

2 atoms that share more than 2 atoms

Diels alder reactions

• are faster when 1 SM has an electron withdrawing group and the other has an electron donating group

Heat

the only necessary reagent for diels alder reactions

exo

substituent points to smaller bridge

endo

substituent points to bigger bridge

limitations to endo/exo

Can not be used for bridges that are the same size

type of reaction diels alder is

• addition reaction

• cycloaddition reactions

number of bonds formed

3 pi bonds → 1 pi + 2 sigma

types of dienes

• isolated: sp3 carbon with no delocalized electrons

• cumulative: sp hybridized carbon

• conjugated: delocalization is possiblr

oxidation of aldehydes in carbohydrates

forms carboxylic acids

reagents of oxidation

• AgNO3, NH3, Ag2O, NaOH

• CuSO4, NaOH,

• Br2,H2O

addition reactions of carbonyls reagents

-CH3OH/cat acid

- PhCh2SH/cat acid

-NaCN/H2O

-RONH2/PH6

-NaBH4/CH3OH

-CH3NH2/PH6

-PhNHNH2/PH6

CH3OH/cat acid

PhCh2SH/cat acid

NaCN/H2O

RONH2/PH6

NaBH4/CH3OH

CH3NH2/PH6

PhNHNH2/PH6

addition and acylation reactions of hydroxyls reagents

-everything is in excess!

-CH3I/NaH

-(CH3O)2SO2/NaOH

-PhCH2Br/NaH

-PhCOCl/N(CH2CH3)3

-CH3COOCOCH3/pyradine

CH3I/NaH

(CH3O)2SO2/NaOH

PhCH2Br/NaH

PhCOCl/N(CH2CH3)3

CH3COOCOCH3/pyradine

reducing sugar

must contain an aldehyde or hemiacetal

N-Terminus protecting groups

use base

BOC2O

CBZ

FMOC

C-terminus protecting groups

use acids (i.e H2SO4)

OtBu

OBn

OMe

DCC

- acylating agent used to form peptide bonds

-helps add amino acids with protecting groups onto other amino acids

isoelectric point

Ph where the molecule carries no electrical charge

Products of diels alder

H2O/H2SO4

- can break acetals/ketals into mixed alcohols

-can not work on OCH2Ph unless it is an anomeric alcohol

CH3OH/H2SO4

-only works on anomeric alcohol

Jones

- creates carboxylic acids

Carboxylic acid

-forms from primary alcohols with water

Aldehyde

- forms from primary alcohols without water

ketone

-forms from secondary alcohols

PCC

PDC

swern oxidation

Hydroboration

- anti-markonikov addition of H2O

Regio: anti-markonikov

Stereo: Syn

Adds: -OH and -H

Common reagents: BH3 or B2H6

Common solvent: H2O2, NaOH

Hydration

- markonikov addition of H2O

Regio: Markonikov

stereo: syn and anti

Adds: -OH and -H

Common reagents: H2O

Common solvents: H2SO4

Halogenation

• anti-addition reaction

Regio: none

stereo: anti

adds: Br2, Cl2, I2, F2, etc.

Halohydrin

• anti-additon reaction

• regio: none

• stereo: anti

• adds: -OH and -X

• common reagents: Br2+H2O , NBS + H2O, Br2+ROH, NBS + ROX

Hydrohalgenation

-addition to alkene

regio: Markonikov

stero: syn and anti

adds: -H and -X

Common reagents: HCl, HBr, HI

Dihydroxylation

Regio: none

stereo: syn

adds: -OH and -OH

Reagent: OSO4 or KMnO4

2nd step: NaOH,H2O or Na2SO3,H2O

Ozonolysis

Regio: none

Stereo: syn

common reagent: 1. O3

Common solvents: 2. Zn or 2.H2O2 or CH3CH3S

Epoxidation

regio: none

stereo: syn

common reagent: RCOOOH

Hydrogenation

- reduction reaction

regio: none

stereo: syn

adds: -H and -H

common reagent: H2

common solvent: Pd/ C

alkynes: H2 will add until fully saturated

Poised Catalyst

-reduction reaction

regio: none

stereo: syn

adds: -H and -H

common reagent: H2

common solvent: pd/BaSO4 w Pbo OR pd/CaCO3 w pbo or quinaline

Dissolving Metal

-reduction reaction

regio: none

stereo: anti

adds: -H and -H

common reagents: Na,Li or K

Common solvent: NH3

Grignard

Ketone → tertiary alcohol

Aldehyde → secondary alcohol

Hydride nucleophile

Ketone → secondary alcohol

Aldehyde → primary alcohol

solvents for NaBH4: CH3OH, H3O+,

solvents for LiAlH4: H3O+, H2O

Organolithium

Ketone → tertiary alcohol

Aldehyde → secondary alcohol

Epoxide opening with weak nucleophiles

- nucleophile reacts to most substituted carbon

-examples: Br2 or H-Br

-H-Br forms alcohol

epoxide opening with strong/basic nucleophiles

-OCH3 reacts to least substituted carbon

-requires a workup (H3O+)

-example: NaOCH3/CH3OH

-forms alcohol

addition of weak nucleophiles to aldehydes

CH3OH/H2SO4

CH3OH/TSOH

additon of weak reversible nucleophiles

Specific acid cat

• protonate

• add

• deprotonate

general mechanism

• Add + Protonate

• deprotonate

specific acid catalyst mechanism

1. protonate

2. add

3. deprotonate

4. protonate LG

5. assisted ionization (elimination)

6. deprotonate

weak base mechanism

3 step

• add

• deprotonate

• LG leaves

5 step

• add

• LG leaves (elimination)

• add

• deprotonate

• elimination of nucleophile

condensation reactions of hemis

condensation reaction of hemis mechanism via sn1

• protonate to make good LG

• LG leaves (assisted ionization)

• addition of nucleophile to carbocation

• deprotonate

condensation reaction of hemiaminal

mechanism of condensation of hemiaminal

hydrolysis reactions

• ketal/acetal + H2O

mechanism of hydrolysis

1. protonate

2. LG leaves

3. Water adds

4. deprotonate water

5. Protonate LG

6. LG leaves

7. deprotonate

intramolecular substitution reactions

Acid Chloride

Anhydride

Carboxylic acid

Ester

Thioester

Amide

Carboxylate

Acylation

• carbon in acyl group is the electrophile

The one reaction

• substitution at the sp2 carbon via addition and elimination

General mechanism for Acylation

1. addition

2. elimination

Tosic acid

Tosylate

Sulfonate ester

Tosyl chloride

benzoic acid

benzoate

Ethyl benzoate

Strong base mechanism

• 2 steps

• anions (-OCH3, -OH, -SCH3)

• no strong acids present

• solvents: CH3OH