Lecture Notes for CM2010 and CM2101 2024 2025 Flashcards
1
Q
What did the late 18th century suggest about organic compounds?
A
Compounds from living organisms were considered organic, while those from lifeless matter were considered inorganic.
2
Q
Who discredited the concept of ‘vital force’ and how?
A
Wöhler discredited the concept by synthesizing urea from ammonium cyanate.
3
Q
What is the empirical formula of lactic acid (C3H6O3)?
A
CH2O
4
Q
What are the main elements that compose the majority of organic substances?
A
Carbon, Hydrogen, and maybe other elements.
5
Q
What does the concept of molecules involve?
A
Atoms of Carbon and other elements connected by covalent bonds.
6
Q
What is Bond Dissociation Energy for Carbon-Carbon bonds?
A
348 kJ mol-1
7
Q
What is unique about Carbon in organic chemistry?
A
Carbon can catenate, forming chains of atoms.
8
Q
Define organic molecules.
A
Carbon-based molecules.
9
Q
What defines organic chemistry?
A
Chemistry of carbon-based molecules.
10
Q
List some properties of organic molecules.
A
- Stability due to C-C covalent bonds
- Defined molecular structures
- Defined three-dimensional shapes
11
Q
Give examples of organic chemicals.
A
- DNA
- Foodstuffs
- Medicines
- Active Pharmaceutical Ingredients
- Excipients
- Fuels
- Materials
12
Q
What are Active Pharmaceutical Ingredients (APIs)?
A
Typically organic molecules of molecular weight < 1000 g/mol.
13
Q
What is the significance of Cork in pharmaceuticals?
A
Cork is a world hub for Pharma.
14
Q
What are the stages of pharmaceutical development?
A
- Lead Discovery
- Pre-Clinical Development
- Phase I & II Clinical Trials
- Phase III Clinical Trials
- Launch & Manufacture
15
Q
What are the aspects of organic molecules?
A
- Structure & bonding
- 3D shape (Stereochemistry)
- Naming (Nomenclature)
- Physical properties
- Chemical properties
- Reactions
- Mechanism
16
Q
What is a Functional Group?
A
The part of a molecule that determines its chemistry and biological profile.
17
Q
List examples of functional groups.
A
- Alkanes
- Ketones
- Amines
18
Q
Identify the first five alkanes by their number of carbon atoms.
A
- 1C: methane
- 2C: ethane
- 3C: propane
- 4C: butane
- 5C: pentane
19
Q
What is the empirical formula of ethane?
A
CH3
20
Q
What is the molecular formula of ethane?
A
C2H6
21
Q
What is the bond angle formed by bonds to a carbon atom in ethane?
A
Approximately 109.5°
22
Q
What does hybridization refer to in organic chemistry?
A
The modification of atomic orbitals to form molecular orbitals.
23
Q
What is the total number of atomic orbitals involved in forming ethane?
A
14 (from 2 Carbons and 6 Hydrogens)
24
Q
What are the types of molecular orbitals formed in ethane?
A
- 7 Bonding molecular orbitals
- 7 Anti-bonding molecular orbitals
25
What is the significance of molecular orbital theory (MOT)?
It helps to model molecules and predict their properties.
26
True or False: All ethane molecules are planar.
False
27
How many total atomic orbitals are contributed by hydrogens in ethane?
6
28
How many molecular orbitals does ethane have?
14
29
What types of molecular orbitals are present in ethane?
* 7 Bonding molecular orbitals
* 7 Anti-bonding molecular orbitals
30
What is the geometry of carbon in ethane?
Tetrahedral
31
What hybridization does carbon undergo in ethane?
sp3
32
What is the tetrahedral angle in ethane?
Approximately 109.5 degrees
33
What is a Newman projection used for?
To define a dihedral angle or torsional angle (φ)
34
What is the torsional angle (φ) in the staggered conformation of ethane?
60 degrees
35
What is the maximum energy conformation of ethane?
Eclipsed conformation
36
What is steric hindrance?
Unfavorable interaction between groups which are close together in space
37
What is the energy difference between eclipsed and staggered conformations of ethane?
12 kJ mol-1
38
What type of bonds does ethane contain?
* C-C single bonds
* C-H single bonds
39
What is the general formula for alkanes?
C_nH_{2n+2}
40
What are the first five alkanes and their molecular formulas?
* Methane: CH4
* Ethane: C2H6
* Propane: C3H8
* Butane: C4H10
* Pentane: C5H12
41
What suffix indicates that a compound is an alkane?
…ane
42
What is the significance of the prefix in alkane nomenclature?
Indicates the number of carbons in the compound
43
What type of structural formula provides information on atom-to-atom connectivity?
Structural formula
44
What is the most stable conformation for simple alkanes at room temperature?
All staggered 'straight chain' conformation
45
What are structural isomers?
Same molecular formulae, different structural formulae
46
How many structural isomers does pentane (C5H12) have?
3
47
What is the concept of a homologous series in organic chemistry?
A series generated by repeatedly adding 'CH2' to the previous member
48
What type of compounds are called straight chain?
Compounds without branches
49
What is an example of a branched alkane?
Isobutane (C4H10)
50
What is the significance of the torsional angle in molecular conformations?
It indicates the degree of rotation about a bond
51
True or False: Ethane contains only sp2 hybridized carbon.
False
52
What are compounds without branches called?
Straight chain
53
How are branched compounds named?
As alkyl derivatives of the longest straight chain in the molecule
54
What determines the parent name in alkane nomenclature?
The length of the longest chain
55
What is the purpose of numbering the straight chain in an alkane?
To indicate the point of branching
56
List the first four alkanes.
* Methane
* Ethane
* Propane
* Butane
57
What is the structure of 2-Methylbutane?
A straight chain numbered to give the lower branch number
58
What are identical substituents grouped with in nomenclature?
'di...' for two, 'tri...' for three, 'tetra...' for four
59
What is the general formula for cycloalkanes?
C_nH_{2n}
60
Which cycloalkane has a planar structure?
Cyclopropane
61
What causes angle strain in cyclopropane?
Bond angles approaching 60°
62
Which cycloalkane has almost zero angle strain?
Cyclopentane
63
What structural form does cyclohexane adopt to reduce strain?
Chair conformation
64
At what temperature can two different types of hydrogen environments be observed in cyclohexane?
Below 230 K (-43 °C)
65
What is the energy barrier to ring inversion in cyclohexane?
43 kJ mol^-1
66
What happens to cyclohexane at temperatures above 230 K?
Only one hydrogen environment is observed
67
What is the effect of replacing a hydrogen in cyclohexane with a methyl group?
The two chair conformations are no longer equivalent
68
What are the steric interactions called between an axial methyl group and 1,3-diaxial hydrogens?
1,3-diaxial interactions
69
What is the main source of alkanes with lower molecular weights (less than 5 carbons)?
Natural gas
70
What type of intermolecular forces are present in alkanes?
London dispersion forces
71
How do alkanes behave in water?
Insoluble; they are hydrophobic
72
What defines unsaturated hydrocarbons?
Contain Carbon-Carbon multiple bonds
73
What are alkenes characterized by?
Presence of Carbon-Carbon double bonds
74
What is the older name for alkenes?
Olefins
75
What is the general structural formula for alkenes?
RRC=CRR
76
What is the bond angle about each carbon in alkenes?
~120°
77
What hybridization is not able to provide the geometry found at carbon in carbon-carbon double bonds?
sp3 hybridization
78
What is the hybridization of alkenes?
sp²
## Footnote
Alkenes cannot provide the geometry found at Carbon in Carbon-Carbon double bonds.
79
What is the bond angle around sp² hybridized Carbon?
Approximately 120°
## Footnote
This angle is consistent with trigonal planar geometry.
80
What type of bond is formed by the overlap of two sp² hybridized orbitals?
σ bond
## Footnote
An antibonding orbital is also formed but is not occupied by electrons.
81
What results from the overlap of pz orbitals in alkenes?
π bond
## Footnote
An antibonding π orbital is also formed but is not occupied by electrons.
82
What is the structure of the Carbon-Carbon double bond?
One σ bond and one π bond
## Footnote
Both bonds are occupied by two electrons.
83
What is required for rotation about a Carbon-Carbon double bond?
Large input of energy (~268 kJ mol⁻¹)
## Footnote
This energy requirement prevents rotation at room temperature.
84
What is Cis-Trans isomerism?
Isomerism due to different spatial arrangements of groups around a double bond
## Footnote
The cis isomer has similar groups on the same side, while the trans isomer has them on opposite sides.
85
What is the first member of the alkene series?
Ethene (Ethylene)
## Footnote
Chemical formula: C₂H₄.
86
What is the second member of the alkene series?
Propene (Propylene)
## Footnote
Chemical formula: C₃H₆.
87
What does the suffix '…ene' indicate in alkene nomenclature?
Presence of a Carbon-Carbon double bond
## Footnote
The prefix indicates the number of carbons.
88
What are structural isomers?
Compounds with the same molecular formula but different arrangements of atoms
## Footnote
Example: 1-Butene and 2-Butene.
89
What is the boiling point of cis-2-butene?
0.3°C
## Footnote
The melting point is -106°C.
90
What is the boiling point of trans-2-butene?
3.7°C
## Footnote
The melting point is -139°C.
91
What type of hybridization do alkynes exhibit?
sp
## Footnote
Alkynes are characterized by the presence of Carbon-Carbon triple bonds.
92
What is the general structure of alkynes?
R-C≡C-R
## Footnote
The groups R and C are co-linear.
93
What is the bond structure of a triple bond in alkynes?
One σ bond and two π bonds
## Footnote
The σ bond forms from sp hybrid orbital overlap, and the π bonds form from p orbital overlap.
94
What is the first member of the alkyne series?
Ethyne (Acetylene)
## Footnote
Chemical formula: C₂H₂.
95
What is the second member of the alkyne series?
Propyne
## Footnote
Chemical formula: C₃H₄.
96
What are nucleophiles?
Electron pair donating species
## Footnote
They react with electrophiles to form new covalent bonds.
97
What are electrophiles?
Electron pair accepting species
## Footnote
They react with nucleophiles in bond formation.
98
What is the order of stability for carbocations?
Tertiary > Secondary > Primary
## Footnote
This stability is due to the inductive effect of alkyl substituents.
99
What is the smallest stable cycloalkyne?
Cyclononyne
## Footnote
Cyclononyne is the smallest stable cycloalkyne.
100
What is the structure and molecular formula of benzene?
6-membered ring system, C6H6
## Footnote
Benzene has a unique structure that contributes to its stability.
101
How do the C-C bond lengths in benzene compare to those in alkenes?
C-C bonds in benzene are 139 pm, while C-C in alkenes are 154 pm and C=C are 134 pm
## Footnote
The equal bond lengths in benzene contribute to its aromatic stability.
102
What hybridization do the carbons in benzene exhibit?
sp2 hybridised
## Footnote
The sp2 hybridization allows for planar geometry and overlap of p orbitals.
103
What concept describes the stability of benzene's electron system?
Aromaticity
## Footnote
Aromatic systems like benzene are especially stable due to resonance delocalization of electrons.
104
What are resonance forms in the context of benzene?
Structures that contribute equally to the overall bonding system
## Footnote
These structures help explain the delocalization of electrons in benzene.
105
What is the general structure of organic halogen compounds?
R-X, where X = Cl, Br, I, F
## Footnote
Organic halogen compounds are important in synthetic chemistry.
106
How are alkyl halides classified?
Based on the degree of substitution: primary, secondary, tertiary
## Footnote
The classification affects their reactivity and properties.
107
What is the molecular formula for ethanol?
C2H5OH
## Footnote
Ethanol is produced through fermentation or hydration of ethylene.
108
What is the difference between absolute alcohol and commercial ethanol?
Absolute alcohol is purified using CaO to remove water
## Footnote
Commercial ethanol typically contains 5% water.
109
What classifies alcohols as weak acids?
R-OH can donate a proton
## Footnote
The acidity of alcohols can be compared with that of phenols.
110
Define the carbonyl group.
C=O functional group
## Footnote
The carbonyl group is a significant functional group in organic chemistry.
111
What are the key differences in nomenclature between aldehydes and ketones?
Aldehydes use 'al' suffix, ketones use 'one' suffix
## Footnote
This distinction helps in identifying the type of carbonyl compound.
112
What is the boiling point of acetaldehyde?
20°C
## Footnote
Acetaldehyde can be prepared from ethylene through the Wacker process.
113
What are the common carboxylic acids mentioned?
* Formic acid (methanoic)
* Acetic acid (ethanoic)
## Footnote
Carboxylic acids are important in various biochemical processes.
114
What are the classifications of amines?
Primary (1°), Secondary (2°), Tertiary (3°)
## Footnote
The classification is based on the number of carbon substituents attached to the nitrogen atom.
115
What is an example of a naturally occurring amine?
Caffeine
## Footnote
Other examples include nicotine and cocaine.
116
What is the general formula for esters?
RCOOR'
## Footnote
Esters are formed from the reaction of an alcohol and a carboxylic acid.
117
What is the significance of the bond dipole in alcohols?
It influences boiling points and solubility
## Footnote
The electronegativity difference between oxygen and hydrogen creates a bond dipole.
118
What is the reactivity of aldehydes and ketones influenced by?
The nature of substituents on the carbonyl group
## Footnote
Different substituents can significantly alter the properties and reactivity of these carbonyl compounds.
119
What is the alternative name for aminopentane?
2-pentanamine
120
What is the structure of 1-methylaminopropane?
CH3NHCH2CH2CH3
121
When other functional groups are present, how is the amino group named?
As a substituent
122
What is the name of the compound with the structure CH3CH(CH2)C(OH)NH2?
3-aminobutanoic acid
123
What is the common name for 4-bromoaniline?
An aromatic amine
124
What is N,N-dimethylaniline categorized as?
An aromatic amine
125
What is Beloranib used for?
Treatment of obesity
126
What type of drug is Furosemide?
A loop diuretic
127
What conditions is Furosemide used to treat?
Congestive heart failure and edema
128
What is Taxol (Paclitaxel) approved for in the UK?
Ovarian, breast, lung, bladder, prostate, melanoma, esophageal, and other types of solid tumor cancers
129
What type of compound is Taxol (Paclitaxel)?
An ester
130
Fill in the blank: How many other Functional Groups can you spot? _______
[key learning term]
