Mcat Orgo Lecture 3

Front 1

*aldehydes and ketones* typically undergo *nucleophilic addition*,

Back 1

while *other carbonyls* undergo *nucleophilic substitution*

Front 2

aldehydes and ketones

Back 2

*** don't H-bond with any cmpd, including themselves***

Front 3

chemical properties of aldehydes and ketones

Back 3

will often act as nucleophilic substrates,

or as a Bronsted-Lowry acids, by **donating one of their alpha-hydrogens**

aldehydes are more acidic than ketones

Front 4

when the B-carbon of a carbonyl is also a carbonyl carbon,

(B-dicarbonyl)

Back 4

the alpha-H gets more acidic, pushing acidity of the aldehyde or ketone > water or alcohol

(normally, they are less acidic)

Front 5

acetals and ketals are used as blocking groups

Back 5

to *prevent* an aldehyde or ketone from *reacting with a nucleophile*

(take an aldehyde, make it an acetal via catalyst, base eventually goes away, return the acetal into an aldehyde by acid)

Front 6

**look for carboxylic acid to behave as either**

Back 6

an acid or a substrate in nucleophilic substitution rxns

look for water leaving

Front 7

**physical properties of carboxylic acids**

Back 7

formation of *dimers* due to H-bonds between two mlcls

- **significantly increases the BP**

Carboxylic acids with more than 10 carbons = insoluble in water

Front 8

tautomerization favors

Back 8

the aldehyde or ketone form

Front 9

acyl chlorides:

Back 9

Bronsted-Lowry acids that donate an alpha-hydrogen

- significantly stronger acids than aldehydes

***most reactive of carboxylic acid derivatives***, because of the stability of Cl LG

***acid chlorides love nucleophiles***

Front 10

hydrolysis can occur under either

Back 10

acidic OR basic conditions

Front 11

determine which one is Beta and which is the main carbonyl by

Back 11

priority

Front 12

strong bases make poor

Back 12

leaving groups

Front 13

in all CA-derivative rxns, the carbonyl carbon acts as the

Back 13

substrate in nucleophilic substitution

Front 14

***all carboxylic acids and their derivatives undergo nucleophilic substitution;***

Back 14

***while all aldehydes and ketones prefer nucleophilic addition***

Front 15

***3 important things to consider when you see cmpds containing nitrogen:***

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1. they may act as Lewis bases, donating their lone pair of electrons

2. they may act as a nucleophile where the lone pair of electrons attacks a positive charge

3. Nitrogen can take on a fourth bond, becoming positively charged

Front 16

when the functional groups are EDG, the trend of amine basicity is:

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2 > 1 > ammonia

Front 17

aromatic amines (amines directly attached to a benzene ring) are:

Back 17

much weaker Lewis bases than nonaromatic amines

because the electron pair delocalizes around the ring

Front 18

amines tend to stabilize carbocations when

Back 18

they are part of the same mlcl, because they donate their electrons

Front 19

ammonia and amines H-bond,

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**raising the BP and increasing solubility**

Front 20

ammonium salt =

Back 20

NH4

an excellent leaving group

Front 21

nitrous acid (HNO2) is a

Back 21

weak acid

nitric acid (HNO3) is a strong acid

Front 22

aliphatic =

Back 22

non-aromatic

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**nitrous acid + primary, aromatic amine =

Back 23

diazonium salt

**only aromatic amines work**

Front 24

amides can behave as

Back 24

weak acids or weak bases;

are hydrolyzed by strong acids or strong bases

Front 25

cyclic amides are called

Back 25

lactams

Beta-lactam = a 4-membered ring

- they are highly reactive due to ring strain

- look for nucleophiles to react with B-lactams