Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Organic Chemistry > Ch 20 - Carbonyl Chem, Organometallic Reagents, Oxi & Red > Flashcards

Ch 20 - Carbonyl Chem, Organometallic Reagents, Oxi & Red Flashcards

0
Q

General reactions of 2 carbonyl classes?

A
  • aldehydes & ketones: nucleophilic addn

* with LG: nucleophilic substitution (Nu replaces Z)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Two classes of carbonyl compounds? (and types in each class)

A
  • only C & H bonded to carbonyl C (aldehydes, ketones - NO LG)
  • EN atom bonded to carbonyl C (carboxylic acids, acid chlorides, esters, amides)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Steps of nucleophilic addn to aldehydes & ketones?

A

1) nucleophilic attack at carbonyl C (Nu = H- or C-)

2) protonation of carbonyl O by water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Steps of nucleophilic substitution of RCOZ?

A

1) nucleophilic attack at carbonyl C (Nu = H- or C-)

2) loss of LG (Z)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Order of reactivity of RCOZ compounds?

A

(best) acid chlorides➡carboxylic acids & esters➡amides (worst)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

3 main redox reaction?

A
  • red aldehydes & ketones ➡alcohols (primary for aldehydes, secondary for ketones)
  • red RCOZ➡aldehydes or primary alcohols
  • oxi aldehydes➡carboxylic acids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Metal reagents used to reduce aldehydes & ketones?

A

• NaBH4 - more selective
• LiAlH4 - more reactive
C=C bonds inert

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Catalytic hydrogenation of aldehydes and ketones (red): reagents? Effects?

A
  • H2/Pd-C

* reduces C=C faster than C=O (both reduced w/excess H2➡alcohols)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Stereochemistry of hydride red of achiral ketone?

A

Racemic mix of 2 alcohols (new stereogenic ctr formed, H behind & H in front, vice versa w/OH ➡ 2 enantiomers)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Activity of metal hydride reagents in RCOZ red?

A
  • NaBH4 - not used (selective for aldehydes and ketones)
  • LiAlH4 - gives 2 H-, more reactive➡alcohols
  • R2AlH (DIBAL-H) - gives one H-, less reactive➡aldehydes
  • LiAlH(OR)3 - gives one H-, less reactive➡aldehydes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Steps of acid chloride & ester red mechanism? 1)➡aldehyde, 2)➡primary alcohol

A

1) nucleophilic substitution - attack of Nu at carbonyl C, loss of LG
2) nucleophilic addn - Nu attack at carbonyl C, protonation of carbonyl O by water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Reagents for red of carboxylic acids➡primary alcohols & amides➡amines?

A

•LiAlH4/H2O

Both C-O bonds red➡C-H bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Reagents used to oxi aldehydes to carboxylic acids?

A
  • CrO3/H2SO4, H2O
  • Na2Cr2O7/H2SO4, H2O
  • Ag2O/NH4OH - selectively oxi aldehydes if compound contains other FGs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

3 types of organometallic reagents? Materials used to form them?

A
  • R-Li (organolithium) - more reactive; RX + 2Li
  • R-Mg-X (Grignard) - more reactive; RX + Mg
  • R2CuLi (organocuprates) - less reactive; 2RLi + CuI
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Ways to form acetylide anions from terminal alkynes?

A
  • H extraction w/NaH➡acetylide anion + Na+ + H2

* H extraction w/CH3Li➡acetylide anion + Li+ + CH4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How do organometallic reagents act as strong bases?

A
  • Abstract H+ from water➡hydrocarbons

* RLi rxt with any OH & NH (esp ROH, RCOOH, RNH2)

16
Q

4 rxns of organometallic reagents as nucleophiles?

A
  • w/aldehydes & ketones (H2O)➡any alcohol
  • w/esters & acid chlorides (H2O)➡ketones or tertiary alcohols
  • w/CO2 (H3O+)➡carboxylic acids
  • w/epoxides (H2O)➡primary alcohols
17
Q

Mechanism for RMX w/aldehydes & ketones?

A

Exactly follows 2 steps of nucleophilic addn (nucleophilic attack & protonation)

18
Q

RMX w/aldehydes & ketones: what SM to make 1)primary 2)secondary 3)tertiary alcohols?

A

1) formaldehyde
2) aldehyde
3) ketone

19
Q

Stereochemistry of RMX rxn w/aldehydes & ketones?

A

Racemic mix of 2 alcohols (new stereogenic ctr formed, R behind & R in front, vice versa w/OH ➡ 2 enantiomers)

20
Q

RMX w/carbonyl compds w/NH or OH: w/protecting group➡? W/out protecting group➡?

A
  • w/PG - 2OHs (C=O➡OH)

* w/out PG - anion (RMX deprotonates interfering OH)

21
Q

3 Steps for using a PG? (RMX w/carbonyl only)

A

1) protection OH w/silyl ether (R-O-TBDMS) & imidazole
2) rxn (RMX, then H2O)
3) deprotect w/Bu4NF

22
Q

esters & acid chlorides➡tertiary alcohols. Reagent?

A

• 2 RMX/H2O
• 2 RLi/H2O
Both very reactive

23
Q

Mechanism for RMX or RLi rxn w/esters & acid chlorides?

A

1) nucleophilic substitution of R w/Z
2) nucleophilic addn of R and H (protonation)
2 R added are the same

24
Q

Rxn acid chlorides ➡ ketones?

A

R2CuLi/H2O (less reactive, don’t rxt w/esters)

25
Q

Stereochemistry of RMX/H2O rxn w/epoxides➡alcohols?

A

Nu attacks at backside of less sub corner of epoxide➡anti, trans OH & R

26
Q

What is an alpha-beta unsaturated carbonyl compd?

A

Conjugated molecules w/carbonyl group (C=O) and C=C, w/single bond in between

27
Q

2 types of rxns of an alpha-beta unsaturated carbonyl compd? Reagents for each?

A
  • 1,2 addn: H & Nu added across C=O➡allylic alcohol (RMgX and RLi, more reactive)
  • 1,4 addn: Nu added to beta C➡carbonyl compd (R2CuLi), less reactive)
28
Q

Mechanisms to know for exam!

A
  • reduction of acid chlorides & esters

* rxn of RLi or RMgX w/esters & acid chlorides

Organic Chemistry (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions