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SEM1 > Organic chem > Flashcards

Organic chem Flashcards

1
Q

Why is organic chemistry largely carbon compounds (2)?

A

1- carbon’s unique ability to form strong covalent bonds with itself
2- carbon’s ability to form 4 covalent bonds

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2
Q

How do we classify compounds?

A

based on their chemical properties: FUNCTIONAL GROUPS

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3
Q

What is the functional group of alkanes and an example?

A

No functional group
Ethane

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4
Q

What is the functional group of alkenes and an example?

A

Double bonded C
Ethene (or ethylene)

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5
Q

What is the functional group of aromatics and an example?

A

Bonded C ring with alternating double/single bond
Toluene

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6
Q

What is the functional group of alkynes and an example?

A

Triple bonded C
Ethyne (or acetylene)

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7
Q

What is the functional group of halides and an example?

A

C bonded to a halogen
Chloromethane

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8
Q

What is the functional group of ethers and an example?

A

-C-O-C-
dimethyl ether

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9
Q

What is the functional group of alcohols and an example?

A

-C-OH
Methanol

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10
Q

What is the functional group of amines and an example?

A

-C-N-
Methylamine

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11
Q

What is the functional group of aldehydes and an example?

A

O=-C-H
Ethanal (or acetaldehyde)

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11
Q

What is the functional group of ketones and an example?

A

O=-C-C
Propanone (or acetone)

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12
Q

What is the functional group of carboxylic acids and an example?

A

=O-C-OH
Ethanoic acid (or acetic acid)

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13
Q

What is the functional group of esters and an example?

A

=O-C-O-C
Methyl ethanoate (or methyl acetate)

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14
Q

What is the functional group of acid chlorides (or acyl chlorides) and an example?

A

O=-C-Cl
Ethanoyl chloride (or acetyl chloride)

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14
Q

What is the functional group of amides and an example?

A

O=-C-N
Acetamide

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15
Q

What are hydrocarbons?:

A

simplest organic compounds containing only C and H

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16
Q

What are saturated hydrocarbons?

A

contain only C–C bonds & therefore max. # of H atoms per carbon atom

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17
Q

What are the two classes of saturated hydrocarbons?

A
  1. Alkanes
  2. Cycloalkanes
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18
Q

What is the formula for alkanes and examples?

A

CnH2n+2 where n = 1, 2, 3, …
methane, ethane, propane

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18
Q

What happens when an alkane has more than 3 carbons?

A

isomers are possible and the number of isomers increases dramatically as the number of carbons increase

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18
Q

What are 3 components to the IUPAC system of nomenclature?

A
  1. Parent – longest chain
  2. Substituents – groups attached to chain
  3. Numbers – used to identify position
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19
Q

How to name alkanes based on numbers of IUPAC

A
  1. Locate longest chain and number each carbon beginning at the end nearest to substituents. 2. Name chain based on the number of C’s.
  2. Indicate the positions of each substituent based on numbers assigned to C’s in chain.
  3. If the same substituent occurs more than once, indicate the frequency by using prefixes:
     di- (2),  tetra- (4),
     tri- (3),  penta- (5), etc.
    and the position number of each substituent.
  4. List substituents in alphabetical order (ignoring the prefixes, di-, tri-, tetra-, etc.)
  5. Punctuation:
     words are not separated
     a word and number are separated by a hyphen
     two numbers are separated by a comma
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20
Q

What are some factors about cyclohexanes?

A

saturated hydrocarbons having a ring of carbon atoms.
group formula: CnH2n
prefix “cyclo” added to parent name
no number is needed for a monosubstituted cycloalkane.
if more substituents, number the ring’s carbons to achieve the smallest # for the substituents.
in more complex compounds, a cycloalkane ring can be treated as a substituent.

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21
Q

What is the formula for Alkenes?

A

CnH2N
(R)2–C = C–(R)2

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21
Q

What is the formula for Alkynes?

A

CnH2n-2
R – C — C – R

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22
Q

What is the nomenclature for alkenes and alkynes?

A

 identify longest chain containing double or triple bond.
 number carbons starting with end closest to the double or triple bond.
 parent name uses “ene” or “yne” instead of “ane”.
 position of double or triple bond indicated by a number preceding the parent name.  indicatesubstituentsasusual.

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22
Q

What are aromatic hydrocarbons?

A

derivatives of the compound benzene

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22
Q

What is the nomenclature of benzene derivatives (aromatic hydrocarbons)?

A
  1. no number necessary for monsubstituents, use common names, e.g., toluene, phenol and benzoic acid
  2. three isomers possible for disubstituents:
     1,2- ortho or “o”
     1,3- meta or “m”
     1,4- para or “p”
  3. when 2 substituents are different, compound named as a derivative of a monsubstituted benzene, i.e., o-chlorotoluene.
  4. when more than 2, use numbers to identify positions: 3,5–dimethylphenol
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23
Q

What are organic halogen compounds?

A

hydrocarbons with halogen substituents
- haloalkanes or alkyl halides
- aryl halides
classified as 1, 2, or 3 according to its C
nomenclature:
F fluoro
Cl chloro
Br bromo
I iodo

EX: CH3CH(Br)CH2Br 1,2-dibromopropane

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23
Q

What are ethers?

A

 derivative of water (HOH)
 structures: R-O-R, R-O-Ar, Ar-O-Ar
 ether group treated as substituents
EX:
CH3–O–CH2CH3 methoxyethane (common name: ethyl methyl ether)
CH3CH2–O–CH2CH3 ethoxyethane (common name: diethyl ether, also known as “ether”)

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24
Q

What are alcohols and phenols?

A

 hydrocarbons with a H atom replaced by OH
 alcohols symbolised by ROH, phenols by ArOH

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24
Q

What is the nomenclature of alcohols and phenols?

A
  1. locate longest chain containing –OH 2. number giving lowest # to –OH group 3. “ane” ending becomes “anol”
  2. give number of –OH position
  3. substituents named before parent
    - an alcohol is classified according to the C it’s attached (i.e., 1, 2, or 3)
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25
Q

What are amines?

A

 derivatives of ammonia (i.e., NH3)
 structures: R-NH2, Ar-NH2, R2NH or R3N
 characterised as 1 , 2, or 3.
 distinct odor
 aliphatic in nature (acid-base chemistry)

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26
Q

What group do aldehydes and ketones both contain?

A

carbonyl (end in aldehydes, middle in ketones)

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27
Q

What is the nomenclature for aldehydes?

A

 number longest chain containing carbonyl.
 carbonyl carbon is number 1.
 group ending: “anal” (i.e., butanal)

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27
Q

What is the nomenclature for ketones?

A

 number longest chain containing carbonyl
 begin numbering closest to carbonyl group
 indicate position of carbonyl group with # preceding the parent name
 group ending: “anone” (i.e., butanone)

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28
Q

What group do carboxylic acids and derivatives have?

A

hydroxyl bonded to acyl
replacement of hydroxyl group with substituents in derivatives

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28
Q

What is the nomenclature for carboxylic acids and derivatives

A
  1. number longest chain with acyl group 2. acyl group understood to be position #1
  2. group ending: alk|ane
    |anoic acid -carboxylic acid (contain –COOH group)
    |anoate -ester and salt (contain –COOR or –COO–M+ group)
    |anamide -amide (contain –COONR2 group)
    |anoyl chloride -acid chloride (contain –COCl group)
  3. name and number substituents in front
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28
Q

How do you distinguish between primary, secondary, and tertiary carbons?

A

 primary (1) – carbon attached to 1 other carbons (i.e., a terminal carbon)
 secondary (2) – carbon attached to 2 other carbons
 tertiary (3) – carbon attached to 3 other carbons

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29
Q

What are structural/constitutional isomers and the 3 types ?

A
  • same molecular formula but different order of the atoms (i.e., different names)
    Skeletal, Positional, Functional
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30
Q

What are isomers?

A

molecules with the same molecular formula

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31
Q

What are skeletal isomers?

A

different arrangements

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32
Q

What are functional isomers?

A

different functional groups

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33
Q

What are positional isomers?

A

different position of substituents

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34
Q

What are cis-trans isomers?

A

CIS- indicates that the substituents are on the same side of the double bond or ring
TRANS- indicates that the substituents are on the opposite sides of the double bond or ring

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35
Q

Effect of cis-trans isomers on properties

A

different melting points, boiling points, density and other physical properties

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36
Q

What are optical isomers?

A

 chiral compounds

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37
Q

What are enantiometers?

A

non-superimposable mirror images

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38
Q

Do optical isomers have the same properties?

A

Identical physical and chemical properties EXCEPT for the sign of the ROTATION

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39
Q

What are the 4 types of Intermolecular forces, their interacting species, and the energy (kj/mol)?

A

Ion-Ion -> only ions -> 250
H bonding -> only hydrides of N, O, F; the link is a shared H atom -> 20
Dipole Dipole -> polar molecules -> 2
London (dispersion) -> all molecules -> 2

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40
Q

Describe London forces

A
  • strength increases with higher molar mass
  • between all molecules (N-P)
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41
Q

Describe Dipole-Dipole

A
  • attractive forces between the positive end of one polar molecule and the negative end of another polar molecule
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42
Q

Describe Hydrogen bonding

A
  • between H bonded to F, N, O
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43
Q

What are the strongest to weakest intermolecular forces

A

H-bonding > Dipole-Dipole > London Dispersion

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44
Q

When do B.P. and water solubility increase?

A

with the strength of the intermolecular forces and the number of functional groups that generate these forces (like dissolves like)

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45
Q

How does branching of the alkane affect the B.P.?

A

lowers the B.P. due to less ordered packing

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46
Q

What does an increase in chain length have an effect on B.P. and water solubility?

A

leads to an increase in b.p. but a decrease in water solubility

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47
Q

What is an electrophile?

A

a positive species that accepts electrons
(i.e., Lewis Acid) e.g., H+ likes to attack a  bond

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48
Q

What is a nucleophile?

A

a negative (e.g., OH–) or neutral species (e.g., H2O or CH3OH) wanting to donate a pair of electrons to a positively charged carbon near an electronegative species, like a halogen (i.e., Lewis Base).

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49
Q

What are free radicals?

A

a neutral species having an extra electron, e.g., Cl

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50
Q

What are the sites for nucleophilic attacks?

A

positive dipole

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51
Q

What are the sites for electrophilic attack?

A

pi bonds

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52
Q

What are reaction intermediates

A

species that are produced and consumed during a reaction but CANNOT BE ISOLATED and do not play a role in the overall chemical equation

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53
Q

Are alkanes reactive?

A

No, due to strength and non-polar nature of bonds

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54
Q

What are the chemical properties of alkanes?

A

 inert to common strong acids (e.g., H2SO4, HCl)
 inert to common strong bases (e.g., NaOH)
 inert to oxidising agents (e.g., MnO4– & Cr2O72–)
 inert to reducing agents (e.g., Na)
* chemistry of alkanes involves free radicals

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55
Q

What are the three types of alkane reactions?

A

pyrolysis, combustion, halogenation

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56
Q

What is a pyrolysis reaction (or cracking)?

A

decomposition of compound by heating usually in presence of a catalyst

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57
Q

What is a combustion reaction?

A

burn in the presence of O2

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58
Q

What is a halogenation reaction?

A

react with a halogen in the presence of U.V. light or heat
- halogen will go towards a tertiary carbon (the carbon with the least amount of hydrogens bonded to it)
- H(halogen) produced

59
Q

What is the halogenation of alkanes?

A

 an example of a very large class of organic rxns known as “substitution reactions”
 Reactivity of halogens: F2 > Cl2 > Br2 > I2
 Preferred order of reactivity with H’s in molecule: tertiary (3) > secondary (2) > primary (1)
 have MAJOR and MINOR products

60
Q

What is a chlorination reaction?

A
  • reaction with Cl2, UV light or heat
  • very difficult to control
  • products separated by fractional distillation
61
Q

What is a bromination reaction?

A

rxn with Br2, UV light or heat

62
Q

What are electrophilic additions?

A
  • bond source of electrons
  • attracts electrophilic agent (i.e. attracts
  • two step process:
    1. Addition of H+ 2. Addition of Nu:-
  • Nucleophile can be Cl-, Br-, I- or H2O
  • So the reagents are HCl, HBr, HI or H+/H2O
  • Preferred position of B-: 3C > 2C > 1C (“Markovnikov’s Rule”)
63
Q

What is a catalytic hydrogenation reaction?

A
  • H2 adds to pi bond in the presence of a catalyst
  • addition to same side of C=C bond
64
Q

What is an addition of halogens (Cl2 or Br2) reaction?

A

double bond broken up by Cl2/Br2, causing them to bond to the two molecules that were previously double bonded

65
Q

What is a polymerization reaction?

A

Polymers: compounds made up of many repeating subunits either naturally or synthetically made.
Monomers: smaller molecule units making up the polymer when linked together.

Polymerization - process by which monomers are combined to form a polymer.

65
Q

What are the 4 reactions of alkenes?

A

electrophilic additions, catalytic hydrogenation, addition of hydrogens (Cl2, Br2), polymerization

66
Q

What is addition polymers?

A

Alkenes are starting materials (monomers) for the large class of polymers

67
Q

How do organic halogen compounds react?

A

Nucleophilic substitution (Nu:- or Nu:)

68
Q

What are organic halogen compounds?

A

 carbon-halogen bond has a large dipole
 carbon (+) site for nucleophilic attack
 important starting materials

69
Q

What is a nucleophilic substitution reaction?

A

 replace halogen with a nucleophile
 used to produce other functional groups
 most general & useful types of rxns
Nu:- is = OH–, NH2–, CN–, SH–, OR–, etc

70
Q

What are some factors about aromatic hydrocarbons?

A
  1. Structure is planar with bond lengths b/w a single & double – resonance hybrid. 2. Benzene ring is VERY stable
  2. Under forcing conditions can hydrogenate.
  3. Need strong catalyst for halogenation with
  4. All six hydrogens acting equivalent.
71
Q

What are the types of reactions of alcohols and phenols?

A

nucleophile formation of acid-base reaction, oxidation

72
Q

What is an oxidation reaction in secondary alcohols?

A

to form ketones

73
Q

What is an acid-base reaction?

A

substitution of OH with the basic atom (ex: Na), H+ bonds to the remaining atom/molecule

74
Q

What is an oxidation reaction in primary alcohols?

A
  • to form aldehydes and carboxylic acids
75
Q

What is an oxidation reaction in tertiary alcohols?

A

no reaction

76
Q

What are factors of ethers?

A

 prepared by nucleophilic substitution
 more hydrocarbon–like than alcohols
 relatively inert
 useful solvents for organic reactions

77
Q

What are factors of amines?

A

 prepared by nucleophilic substitution
 basic in nature (acid-base chemistry)
 used to form amides (later reaction)

78
Q

What is the oxidation of aldehydes?

A

Aldehydes readily oxidise to carboxylic acids but ketones, under same conditions are NOT oxidised

79
Q

What is the reduction of aldehydes and ketones?

A
  • electrophilic attack
     aldehydes reduces to 1o alcohols.
     ketones reduces to 2o alcohols
    Other reducing reagents: NaBH4 then H+/H2O LiAlH4 then H+/H2O
    *H2/Pt
80
Q

What happens if water is added to nucleophilic addition?

A

(forms a geminal diol - hydroxyl groups bonded to the same atom)

aldehyde/ketone + H2O -> hydrate/geminal diol

81
Q

What happens if alcohols are added to nucleophilic addition?

A

 leads to hemiacetals
 equilibrium usually favours the carbonyl compound and the alcohol
CH3C(O)CH3 + HOCH2CH3  CH3C(OH)(OCH2CH3)CH3

82
Q

How can you test if a compound is either an aldehyde or ketone?

A

 use Tollens reagent (Ag+ in NH3)
Aldehydes: CH3CHO + Ag+ -> CH3COOH + Ag(s)
Ketones: CH3C(O)CH3 + Ag+ -> no rxn

83
Q

What are some factors of carboxylic acids and derivatives?

A

 carbon-oxygen bond has a large dipole
 carbon (+) site for nucleophilic attack

84
Q

What do carboxylic acids react with?

A
  • they are week acids, react with strong bases
  • placed in water produces acidic solutions
85
Q

How are carboxylic acids prepared?

A
  • OXIDATION of 1 alcohols or aldehydes with Cr2O72– /H+
86
Q

How are ethers prepared?

A

A. Direct Esterification (Acid + Alcohol):
RCOOH + R’OH -> H2O + RCOOR’
B. Acid anhydride + Alcohol:
ROC(O)OC(O)OR’ + R’OH -> ROCOOH + R’OCOOR’

87
Q

What does the hydrolysis of esters result in?

A
  • aka saponification
  • formation of salts
    RCOOR’ + NaOH -> RCOO-Na+ + R’OH
88
Q

How do you prepare amides?

A

A. acid + amine → amide + water BUT it doesn’t work very well!!
B. ester + amine  amide + alcohol

89
Q

What are condensation polymers?

A
  • polyesters and polyamides
  • monomers have two functional groups (diols, dicarboxylic acids, diacid halides, etc.)
90
Q

What are polyesters?

A

ester formation reaction
dicarboxylic acid + diol + H+ → polyester + H2O
Can also use molecules having both functional groups

91
Q

What are polyamides?

A
  • amide formation reaction
    diester + diamine → polyamide + alcohol
  • proteins are natural polyamides
92
Q

What are organic compounds as acids?

A

 acidic H’s are attached to electronegative atoms (e.g., oxygen)
 electron withdrawing effects increase the acidity of a hydrogen
 order of decreasing acidity:

93
Q

What are organic compounds as bases?

A
  • atoms with lone pair electrons can act basic if willing to donate them to a proton (H+)
  • organic bases tend to be nitrogen compounds
94
Q

What is the salt formation from organic compounds as acids/bases?

A

A. organic acid/base + base/acid -> organic salt
B. organic salt + acid/base -> organic acid/base

95
Q

What are stereoisomers?

A
  • compounds that are isomers because of different arrangements in space
  • atoms attached to particular carbon in one isomer are attached to the same carbon in the other isomer
96
Q

When is there free rotation around a sigma bond?

A

When carbon atoms attach by a single sigma bond
- if carbon atoms are attached by a double bond, the pi bond prevents free rotation

97
Q

What does a lack of free rotation mean?

A

substituents around the two carbons involved in the double bond can have different spatial arrangements

98
Q

What are cis-trans (geometric isomers)?

A

cis: substituents are on the same side
trans: substituents are on opposite sides

99
Q

Do geometric isomers have the same physical and chemical properties?

A

No

100
Q

Which arrangement is more favourable + which is made in nature?

A
  • trans
  • nature produces molecules with double bonds in CIS form
101
Q

Where else can geometric isomers be found?

A

cycloalkanes

102
Q

What is plane polarized light and how is it obtained?

A
  • consists of waves vibrating in one plane
  • obtained by passing ordinary light through a certain kind of material
  • waves vibrating in one orientation
103
Q

What is a polarimeter used for?

A

to measure the interaction of a chiral compound with plane polarized light

104
Q

What does dextrorotatory mean?

A

plane rotated clockwise (+)

105
Q

What does levorotatory mean?

A

plane is rotated counterclockwise (-)

106
Q

What does chiral mean?

A

optically active
- cannot be superimposed on its mirror image

107
Q

What is the most common type of chiral compounds?

A

contain carbon atom bounded to 4 different groups
- it is an asymmetric carbon/carbon centre

108
Q

Can you have an asymmetric carbon at a double bonded carbon?

A

No

109
Q

When do mirror images become superimposable?

A

two or more substituents are the same

110
Q

What are enantiomers?

A

pair of non-superimposable mirror images

111
Q

Do enantiomers have the same physical and chemical properties?

A
  • Same physical
  • Same chemical, except in the way they react/interact with other chiral molecules
  • Different physiological properties
112
Q

How do enantiomers interact with plane polarized light?

A

equal but opposite directions

113
Q

What are configurations?

A

arrangements in space of the four groups attached to an asymmetric carbon

114
Q

How many spatial arrangements can an asymmetric carbon have?

A

two; total number of isomers that can result given by 2^n (n is number of asymmetric carbons)

115
Q

What do chemical properties indicate

A

whether molecule interacts with positive agent (electrophile) or negative agent (nucleophile)

116
Q

What is an positive agent?

A

electrophilic / electron lover

117
Q

What is a negative agent?

A

nucleophilic agent / nucleus lover

118
Q

What determines if a molecule interacts with positive or negative agent?

A

whether the molecule has pi bonds or present dipoles

119
Q

What law do electrostatic interactions follow?

A

Coulomb’s law : the greater the charges, the greater the electrostatic attractions

120
Q

What are dipoles generated in a particular bond depend on?

A
  • number of electrons around atoms involved
  • difference in electronegativity between the atoms involved in the bond
121
Q

What is the order of strongest to weakest intermolecular force + lowest to highest boiling point?

A

H > Dipole-dipole > London

122
Q

What happens to the BP if the number of groups increases in a compound?

A

increases

123
Q

What is the saying for water solubility?

A

like dissolve like,
H > dipole-dipole > london

124
Q

What happens if the functional group remains the same but the number of carbon increases (water solubility)?

A

amount of London forces increases; water solubility decreases

125
Q

What are the common attacking agents?

A

electrophilic, nucleophilic, free radicals

126
Q

What are electrophilic agents?

A

positive species that wants to go to a site that has available electrons and wants to accept electron pair- often a pi bond

127
Q

What is a nucleophilic agents?

A

either a negative species, or neutral species which has a free pair of electrons (a lewis base)

128
Q

What are free radicals?

A

neutral species that has unpaired electron; react by abstracting an atom from molecule or by combining with a compound containing a multiple bond

129
Q

What happens to a reaction if the intermediate is more stable?

A

the more likely the intermediate, the more likely it is to be produced and thus the more likely the reaction is to occur

130
Q

what is the most common types of intermediates?

A

tervalent carbons (carbon atoms with 3 bonds)

131
Q

What is the preferred site for chemical reactions in alkanes?

A

none; as it is essentially non-polar

132
Q

What are the common reactions for alkanes?

A

combustion
substitution of H by halogen

133
Q

What are the common reactions for alkenes?

A
  • electrophilic addition
  • hydrogenation
  • polymerization
134
Q

What is the common reaction for haloalkanes (alkyl halides)?

A
  • substitution of X
135
Q

What is the common reaction for benzene rings?

A
  • substitution of H (must have catalyst)
136
Q

What are the common reactions for alcohols?

A
  • oxidation
  • metal salt formation
  • condensation polymers
137
Q

What are the common reactions for amines?

A
  • salt formation
  • condensation polymers
138
Q

What are the common reactions for aldehydes?

A
  • oxidation and reduction
  • nucleophilic addition
139
Q

What are the common reactions for ketones?

A
  • reduction
  • nucleophilic addition
140
Q

What are the common reactions for carboxylic acids?

A
  • salt formation
  • reduction
  • substitution (condensation with alcohol)
  • condensation polymers (diacid + diol)
141
Q

What is the common reaction for esters?

A
  • condensation polymers
142
Q

How does electrophilic additions happen for alkenes and alkynes?

A
  • pi bond is source of loosely held electrons, offers reactive centre for attack for an electrophilic agent
  • two steps (electrophilic agents attaches to one carbon in double bond, produces carbocation which attaches to nucleophilic agent)
  • A+ and B- add to carbons involved in double bond, no pi bonds left
    ADDITION
143
Q

What is the order of preference for the nucleophilic agent in alkenes/alkynes?

A

3C, 2C, 1C
(tertiary, secondary, primary carbon)

144
Q

How does hydrogenation occur?

A
  • hydrogen bonds to pi bond in presence of Pt, Pd,
    or Ni
  • occurs at surface of catalyst and two hydrogens added simultaneously to same side of double bonded C
145
Q

What is a polymerization reaction?

A
  • alkenes get grouped together: addition polymers
  • initiators are free radical, which generates free radical
    0 free radical interacts with monomer in series of repeating steps or chain reaction (initiation step, propagation step)
146
Q

How do haloalkanes (alkyl halides) react?

A
  • C-H bond has large dipole due to electronegativity differences
  • S+ on carbon makes it prone to attack by nucleophilic agents
    NUCLEOPHILIC SUBSTITUTION
147
Q

What are aromatic substitutions?

A
  • more difficult to carry out due to stable nature of aromatic structure
  • require catalysts (H2SO4, FeCl3, FeBr3)
  • first substituent (if present) dictates where the second one goes
    EX: nitrations, halogenation
148
Q

How do alcohols react?

A

oxidation (using K2Cr2O7, Na2Cr2O7, or Cr2O7^-2) under acidic conditions
- different results obtained depending on nature of starting alcohol

149
Q

What is a metal salt formation?

A
  • to convert alcohols into stronger nucleophilic reagents (base such as NaNH2, or Na metal can be added)
150
Q

Are carbonyl groups in aldehydes in ketones prone to attack by electrophilic or nucleophilic agents?

A

both

151
Q

What is a reduction reaction?

A
  • opposite of oxidation of 1 and 2 alcohols to aldehydes and ketones
  • reduced back to corresponding alcohols
  • makes use of reactivity of pi bond in carbonyl group towards H in presents of Pt catalyst
  • also carried out by two-step process using NaBH4 or LiAlH4
152
Q

What is a nucleophilic addition reaction for aldehydes and ketones?

A
  • presence pi bond and dipole in carbonyl group is basis for reactions occuring with aldehydes and ketones
153
Q

How can carboxylic acids and derivatives be produced?

A
  • starting point is carboxylic acid that can be readily prepared by oxidation of a 1 alcohol
154
Q

How can esters be prepared?

A

condensation of an acid and an alcohol

155
Q

What is a simple way of preparing amides?

A

exchange of alcohol portion of an ester with an amine

156
Q

How are condensation polymers prepared?

A
  • same as esters and amides
  • **must have at least two functional groups to allow polymer change to grow
  • polyesters or polyamides
157
Q

Are organic acids and bases strong?

A
  • not nearly as much as inorganic acids and bases
158
Q

How can you get an organic acid?

A
  • generate acidic H+ in organic compound, which must be attached to electronegative atom (most often oxygen)
  • nature of other group on oxygen atom can have noticeable effect of acidity of hydrogen
159
Q

How can you get an organic base?

A
  • behave as base if it has a free pair of electrons that it can donate to a hydrogen atom
  • tend to be nitrogen compounds
160
Q

How are salts generated?

A

when an organic acid/base are reacted with its opposite inorganic acid/base

SEM1 (3 decks)

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