Organic Chemistry II Exam 3: Chapter 20, 21, 22, 23

what are the three ways we learned to synthesize carboxylic acids

1. hydrolysis of nitriles

2. carbonaiton of organometallics

3. oxidation

What is the the reaction for the hydrolysis of nitriles

RCN ----> (1. NaOH, H2O, 2. H3O+) --> RCO2H

RCN --- (H3O+) --> RCO2H

What is the mechanism for the acidic hydrolysis of the nitrile

1. protonate the nitrogen

2. attack the triple bond with water and then transfer one of the pi bonds onto the nitrogen (should be left with OH2, R, and NH)

3. protonate the nitrogen with one of the H2 of OH2

4. attack with water and transfer electrons onto the nitrogen

5. protonate NH2 with an H from OH2

6. have electrons from OH go down and then have NH3 leave

7. deprotonate

What is the mechanism for the basic hydrolysis of nitriles

1. attack triple bond with OH and then have the pi bonds move onto the nitrogen

2. protonate the nitrogen (should have a negative charge) and then form OH-

3. depronate the OH and put electrons onto the oxygen

4. transfer the electrons from the oxygen down and then have the double bond be protonated by water - will be left with an amide

5. then you will have OH- come in and attack and form CR, NH2, OH, O

6. have the electrons go down the O- and then have NH2 leave

7. because basic conditions should be R-C=O,OH

what is the general formula for carbonation of organometallics

RMgX/RLi

1. CO2

2. H3O+

RCO2H

what is the mechanism for the carbonation of organometallics

1. form the grignard reagent

2. have the grignard attack O=C=O

3. protonate the oxanion

What is oxidation for forming carboxylic acid

1. alkyl benzene - can react with KMNO4 H2)

2. primary alcohol can react with CrO3 and H3O+

what are the three ways we learned how to synthesize nitriles

1. SN2 displacement

2. cyanohydrins

3. dehydration of amids

what is the reactant necessary for the formation of a cyanohydrin from a ketone

KCN, H2SO4 or HCN

What happens when you react RCN with 1. LiAlH4 and H2O

RCH2NH2

what happens when you react RCN with 1. R'Li and 2. H3O+

forms a ketone

What is the mechaism for RCN + 1, LiALH4 2. H3O+

1. the n itrile takes an H from AlH4 and then transfers an electron onto the N

2. then the nitrogen is negatively charged and then AlH3 attaches to the N

3. add water

What is the mechanism for adding a grignard to an ester

3 main steps: nucleophilic addition, imine formation, and hydrolysis

1. girgnard attacks and the pi electrons transfer onto the n

2. and then protonate the nitrogen

3. then protonate the nitrogen again and then have the h3O+ say that is not positive and then the electrons transfer onto the nitrogen n

4. protonate the H of NH2 with the OH2

5. then OH with left with chain -

6. then have the OH go down and have NH3 leave

7. depronate the oxygen

how do you form an acid chloride

carboxylic acid + SOCl2

mechanism for the formation of the acid choride from carboxylic acid

carboxylic acid + SOCl2

mechanism for the formation of an acid chloride

so the Cl- attacks C and then puts electrons on oxygen for negative charge

then the oxygen moves it down and then the other bond goes to the other side so pretty similar to th eoutcomes

Fischer esterification - which reactants

ROH in HCl `

what is the mechanism for fischer esterification

1. protonate oxygen

2. attack with R OH

3. then oxygen goes down adn the Oh2 moves away

4. OH2 gets rid of hydrogen

5. protonate the oxygen

6. the Oh2 goes again

7. electrons go down

8. depronate the oxygen

what reactants are used to form an amide from a carboxylic acid

1. DCC

2. R'NH2

what is the mechanism for formation of an amide from carboxylic acid

(review the sheet page 4)

what are the reactants for reduction of RCO2H + RCH2OH

if react with 1. BH3, THF 2. H2O - faster

if react with lialh4 2. h3O+

what is needed to hydrolyze acid chloride

react with water

what is mechanism for hydrolyis s of acid chloride

add water

2. electrons from O- go down adn cl leaves

3. Cl- deprotonates Oh2

estherification of acid chloride - what are the reactants

r'OH and pyridine

ihow do you replace a primary OH with AcO

1. CH3OCl 2. pyridine

what reactants are necessary for aminolysis of an acid chloride

2 equivalents of 2 R'NH2

what is mechanisms of aminolysis - amide formation

1. pyridiine deprotonates the H from NHR1

2. nitrogen attacks

3. electrons shift down forming a dance arena

how do you reduce an acid chloride

1. add LiAlH4

2. add RMgX

what is ketone synthesis from acid chloride

have the oxgen come down and Cl leave

have it go away

what happens with Ac2O + ROH --pyridine --> RoAC + ACO

What happens with Ac2O +RNH2 ---> RNHAC + ACO -

what is needed for basic esther hydrolysis

hydroxide

what is the mechanism of basic esther hydrolysis

1. oh attacks and then it only got one and it was nice

what is needed for aminolysis of esther

RNH2

what is the mechanism for it

N attacks

o shifts down and OR leaves

RO is on a run and took H from NH2

how do you do transesterhification but alcoholysis

have the RCO2Me and the ROH

what is the reduction of an esther - what is needed

LiALH4 and 2. h3o+

how many equivalents of griganrd do you need for esthers

2

what happens with grignard and esther

R-Li attacks and the O4 leaves and then the R-Li attacks again and then h3O+

hydrolysis of amide two ways

1. H3O+

1. OH-

hydrolysis of amide (acidic

hydrolysis of amid (basic)

how do you reduce an amide

1. LIALH4 2. H2O

mechanism for reduction of amide

ALH4 enters and shifts oxygen

then the nitrogen stuff into it and onto oxygen

get rid of double bond and then it forms

if you want to reduce an esther into an alcohol which reactant should you use `

LiAlH4 H3O+

if you want to reduce an esther into an aldehyde which reactant should you use

(i-bu)2AlH

2. H3O+