Organic Chemistry II Flashcards
What are the prefixes for the first 12 alkanes?
Meth, eth, prop, but, pent, hex, hept, oct, non, dec, undec, dodec.
What are the 5 steps used to name alkanes according to IUPAC rules?
- Find the longest chain. 2. Number the chain so that the lowerst set of numbers is obtained for the substituents. 3. Name and alphabetize the substituents. 4. Assign a number to each substituent. 5. Complete the name.
In case of an “en-ol”, which carbon recieves the lowers number?
The carbon attached to the alcohol group is assigned the lowest number.
What is a diol?
A diol is a molecule with two hydroxyl (OH) groups.
T/F, an aldehyde has a carbonyl group somehwere in the middle of a carbon chain?
False, in an aldehyde, the carbonyl group is at the end of the carbon chain.
T/F, a ketone has the carbonyl group at one end of a carbon chain?
False, in a ketone, the carbonyl group is somehere in the middle of the carbon chain.
In the case of an “en-one”, which carbon recieves the lowest number?
The carbonyl carbon receives the lowers number.
What type of compound does a -COOH group deonote?
The COOH group denotes a carboxylic acid.
What is the common name for methonoic acid?
Methanoic acid = formic acid.
What is the common name for ethanoic acid?
ethanoic acid = acetic acid
What is the common name for propanoic acid?
Propanoic acid = propionic acid
Name RC≡N:
Nitrile / Cyanide
Name RSH
Thiol
Name R₂S
Sulfide.
Name RNO₂
Nitro.
Name RN₃
Azide.
Name RN₂+
Diazo.
Name the prefix and suffix for Carboxylic Acid?
Carboxy- / -oic acid
Name the prefix and suffix for Ester.
alkoxycarbonyl- / -oate
Name the prefix and suffix for Acyl Halide?
halocarbonyl- / -oyl halide
Name the prefix and suffix for Amide.
amido- / -amide
Name the prefix and suffix for Nitrile?
cyano- / -nitrile
Name the prefix and suffix for Aldehyde?
oxo- / -al
Name the prefix and suffix for Ketone?
oxo- / -one
Name the prefix and suffix for Alcohol?
hydroxy- / -ol
Name the prefix and suffix for Thiol?
sulfhydryl- / -thiol
Name the prefix and suffix for Amine?
amino- / -amine
Name the prefix and suffix for Ether?
alkoxy- / -ether
Name the prefix and suffix for Sulfide?
alkylthio- / -sulfide
Name the prefix and suffix for Nitro?
nitro- / ~
Name the prefix and suffix for Azide?
azido- / -azide
Name the prefix and suffix for Diazo?
diazo- / ~
What is a strctural isomer?
Structural isomers have the same chemical formulas, but different atomic connectivity.
What is a stereoisomer?
Stereoisomers are compounds that differ only in respect to the spatial arrangement of their atoms.
Order the following conformations of n-butane according to energy elvels (low to high): gauche, anti, eclipsed, totally eclipsed.
Anti, gauche, eclipsed, totally eclipsed.
What are the three cyclic hexane conformers?
Chair, boat, twisted boat.
Order the three cyclo hexane conformers according to energy levels?
Low to High: Chair, twisted boat, boat.
T/F, axial hydrogens are parallel to the ring?
False, axial hydrogens are perpendicular to the ring.
T/F, bulky groups prefer the equatorial position over the axial position?
True.
What are geometric isomers?
Geometric isomers are molecules that differ with respect to the spatial relationship of substituents around a double bond.
What is a chiral molecule?
A chiral molecule is a molecule that is not superimposable upon its mirror image.
What are enantiomers?
Enantiomers are chiral molecules that are non-superimposable mirror images of each other.
T/F, achiral moleules are optically active?
False, achiral molecules are optically inactive.
What is a dextrorotatory (+) compound?
A dextrorotatory compound rotates polarized light to the right (clockwise)
What is a levoratory (–) compound?
A levorotatory compound rotates polarized light to the left (counterclockwise).
What is a racemic micture?
A racemic mixture contains equal amounts of both enantiomers.
How many stereoisomers are possible for a molecule with four chiral centers?
2^n2^4 = 16
What are diastereomers?
Diastereomers are stereoisomers that are not mirror images of each other.
What types of molecules are optically active?
Chiral molecules are optically active.
What is a meso compound?
A meso compound is a molecule that possesses stereocenters but has a plane of symmetry. It is achiral and therefore optically inactive.
What type of chemical bond involves the sharing of electrons?
Covalent bonds involve the sharing of electrons.
What type of chemical bond involves the transfer of electrons?
Ionic bonds involve the transfer of electrons.
Which orbital has a spherical shape?
”s” orbitals are spherically shaped.
Which orbital has a bi-lobed shape?
“p” orbitals are bi-lobed.
T/F, all single bonds are sigma bonds?
True.
What type of bond results when two p orbitals overlap?
Two overlapping p orbitals form a pi bond.
What are the components of a double bond?
A double bond is composed of 1 sigma and 1 pi bond.
What are the components of a tripple bond?
A tripple bond is composed of 1 sigma and 2 pi bonds.
T/F, a pi bond can exist without a sigma bond?
False, a pi bond cannot exist independently of a sigma bond.
Which type of bond (pi or sigma) is stronger?
A sigma bond is generally stronger than a pi bond.
What is the hybridization of the carbon atom in CH4? What are the bond angles?
sp^3, 109.5º
What is the bond angle between sp hybridized atoms?
180º
What is the bond angle between sp^2 hybridized atoms?
120º
What is the general formula of a noncyclic alkane?
The general formula of an alkane is (Cn)(H2n)+2
How many other carbons are 1º, 2º, 3º and 4º carbons bonded to?
1, 2, 3, and 4 other carbons respectively.
How does increasing molecular weight affect the boiling point and melting point of an alkane?
Increased molecular weight results in increased boiling and melting points.
How does increased branching affect the boiling point of an alkane?
Increased branching lowers the boiling point.
What are the three steps of a halgenation reaction?
The three steps of halogenation are: initiation, propagation, and termination.
Which step of halogenation does the following reaction represent? X₂ ––hv or ∆––➜ 2X●
Initiation
Which step of halogenation does the following reaction represent? 2X● ––––➜ X₂
Termination.
Which step of halogenation does the following reaction represent? R● + X₂ ––––➜ RX + X●
Propagation.
Which step of halogenation does the following reaction represent? X● + R● ––––➜ XR
Termination.
Which step of halogenation does the following reaction represent? X● + RH ––––➜ HX + R●
Propagation.
Which step of halogenation does the following reaction represent? 2R● ––––➜ R₂
Termination.
What is the order of free radical stability?
3º > 2º > 1º> methyl.
What type of reaction involves breaking down large alkanes into smaller ones?
Pyrolysis or “cracking” uses heat to break down large alkanes into smaller ones.
What are the products of the complete combustion of an alkane?
The complete combustion of an alkane produces: CO2, H2O, and heat.
Is a nucleophile electron rich or elctron poor?
A nucleophile is electron rich.
All else being equal, how does basicity affect the strength of a nucleophile?
The stronger the base, the stronger the nucleophile.
How many steps are involved in an SN1 reaction? What are they?
There are two steps in an SN1 reaction:1st, the molecule dissociates into a carbocation and a leaving group.2nd, the nucleophile combines with the carbocation.
What is the order of carbocation stability?
3º > 2º > 1º > methyl.
Which step in an SN1 reaction is the rate determining step?
The first step, the formation of the carbocation, is the rate determining step.
T/F, the rate of an SN1 reaction is dependent on the concentration of the nucleophile?
False, the rate is only dependent on the concentration of the original molecule.
How can SN1 reaction rate be increased?
1, stabilize the carbocation by increasing substitution and using a highly polar solvent. 2, use a better leaving group (weak base).
How does basicity affect the nature of a leaving group?
The weaker the base, the better the leaving group.
How many steps are invovled in an SN2 reaction?
SN2 reactions have one step.
Is the rate of an SN2 reaction dependent on the concentration of the substrate, of the nucleophile, or both?
The SN2 reaction rate is dependent on the concentration of both the substrate and the nucleophile.
T/F, SN1 reactions involving a chiral substrate produce an optically active mixture.
False, a racemic mixture results during SN1 reactions with an optically active reactant.
T/F, SN2 reactions involving a chiral substrate result in an inverted, optically active product.
True.
Which type of reaction is favored (SN1 or SN2) given the following condition: Polar protic solvent?
Polar protic solvents favor SN1.
Which type of reaction is favored (SN1 or SN2) given the following condition: Polar aprotic solvent?
Polar aprotic solvents favor SN2.
Which type of reaction is favored (SN1 or SN2) given the following condition: Methyl or 1º alkyl halide?
Methyl or 1º alkyl halides favor SN2.
Which type of reaction is favored (SN1 or SN2) given the following condition: 3º alkyl halide?
3º alkyl halides favor SN1.
T/F, E1 and SN1 reactions are driven by the same factors: Polar solvent, good leaving groups, highly branched chains, etc…?
True.
Which form of an alkene has a higher melting point (cis or trans)?
The trans form of an alkene has a higher melting point due to its symmetry.
Which form of an alkene has a higher boiling point (cis or trans)?
The cis form of an alkene has a higher boiling point due to its polarity.
2, 3- dibromobutane ––base, ∆–––> ???
but-2-yne
T/F, the reduction of an alkyne on a metal surface (Pd) results in a cis alkene?
False. It results in an alkane.
T/F, the reduction of an alkyne in Na and NH3 produces a trans alkene?
True.
Does the electrophilic additionof HBr to an alkyne follow Markovnikov’s rule?
Yes, electrophilic addition of Hbr to an alkyne or an alkene follows Markovnikov’s rule.
Does the free radical addition of HBr to an alkyne follow Markovnikov’s rule?
No, free radical addition of HBr to an alkyne or an alkene does not follow Markovnikov’s rule.
Cyclobutene ––––mcpba–––> ???
epoxide –(four membered ring still conserved with both 1,2 substituents sharing, or connected by, an oxygen).
What is an aromatic compound?
An aromatic compound is defined as any unusually stable ring system. Aromatic compounds are:1. Cyclic2. Conjugated polyenes3. Follows Huckel’s rule (4n + 2) pi electrons
What is an aliphatic compound?
An aliphatic compound is any non-aromatic compound.
What is Huckel’s rule?
Huckel’s rule states that an aromatic compound has (4n + 2) pi electrons, where n is any non-negative integer.
What is an antiaromatic compound?
An anti-aromatic compound is a cyclic conjugated polyene with 4n electrons.
What is the difference between a phenyl and a benzyl group?
A benzene ring acting as a substituent is called a phenyl group(–C6H5). A toluene molecule substituted at the methyl position is called a benzyl group (–CH2C6H5).
What is the name of a methyl substituent on a benzene ring?
Toluene.
What is the common name for a NH2 substituent on a benzene ring?
Aniline.
What is the common name an OH substituent on a benzene ring?
Phenol.
Do electron donating groups activate or deactivate an aromatic ring?
Electron donating groups activate a ring.
How do electron withdrawing groups affect the reactivity of an aromatic ring?
Electron withdrawing groups deactivate a ring.
Is COOH activating/deactivating and ortho/para directing or meta directing?
Deactivating / meta
Is NR2 activating/deactivating and ortho/para directing or meta directing?
Activating / o-p
Is NH2 activating/deactivating and ortho/para directing or meta directing?
Activating / o-p
Is NO2 activating/deactivating and ortho/para directing or meta directing?
Deactivating / meta
Is F, CL, Br and I, activating/deactivating and ortho/para directing or meta directing?
Deactivating / o-p
Is COOR activating/deactivating and ortho/para directing or meta directing?
Deactivating / meta
Is OR activating/deactivating and ortho/para directing or meta directing?
Activating / o-p
Is SO3H activating/deactivating and ortho/para directing or meta directing?
Deactivating / meta
Is OCOR activating/deactivating and ortho/para directing or meta directing?
Activating / o-p
Is CH3 activating/deactivating and ortho/para directing or meta directing?
Activating / o-p
T/F, activating compounds are always o-p directors?
True.
T/F, deactivating compounds are always meta directors.
False, halogens are deactivating and are o-p directing.
Why do alcohols have a significantly higher boiling point than analogous alkanes?
Alcohols can hydrogen bond.
T/F, phenols are less acidic than aliphatic alcohols?
False, phenols are much more acidic than aliphatic alcohols.
What are the three types of reactions used to sythesize alcohols?
The three general types of reactions used to prepare alcohols are: addition, substitution, and reduction.
Can a teriary alchohol be easily oxidized?
No, tertiary alcohols cannot be oxidized without cleavage of a carbon-carbon bond.
Can ethers hydrogen bond?
No, ethers do not hydrogen bond.
How does the boiling point of an aldehyde (or ketone) compare with its analgous alkane? alcohol?
The boiling point of an aldehyde is higher than that of the corresponding alkane but lower than that of the corresponding alcohol.
How is a ketone or an aldeyhde produced from an alcohol?
Oxidizing an alcohol will produce the corresponding ketone or aldehyde (i.e., by using PCC, or Na2Cr2O7).
How do you produce a ketone or aldehyde from an alkene?
Ozonolysis of an alkene will produce corresponding ketones or aldehydes as cleavage products.
Which protons relative to a carbonyl group are acidic?
Alpha protons relative to a carbonyl group are slightly acidic.
What happens when aldehydes or ketones react with water?
Aldehydes and ketones react with water to form gem-diols.
T/F, a reacttion in which two moleles combine with the the loss of a water molecule is a condensation reaction?
True.
What would be the product when an acetaldehyde is reacted with dilute NaOH?
Aldol.
What is the reaction called when an acetaldehyde is reacted with dilute NaOH?
Aldol condensation to produce an aldol.
How do electron withdrawing groups (–Cl, –NO2) attached to the alpha carbon affect the acidity of a carboxylic acid?
Electron withdrawing groups increase acidity.
How do electron donating groups (–NH2, –OCH3) attached to the alpha carbon affect the acidity of a carboxylic acid?
Electron donating groups decrease acidity.
Would you have to oxidize or reduce an aldehyde to create a carboxylic acid?
Oxidation of an aldehyde creates a carboxylic acid.
What are the common names for the first three strait chain carboxylic acids?
The first three carboxylic acids are: Formic acid, acetic acid and propionic acid.
T/F, alcohols have higher boiling points than carboxylic acids?
False, carboxylic acids have higher boiling points than corresponding alcohols.
T/F, vacuum distillation can be used to separate liquids with very high boiling points?
True.
Which separation technique separates compounds based upon their different affinities for a medium?
Chromatography separates compounds based on their different affinities for a medium.
What is the Rf value in thin layer chromatography (TLC)?
The Rf value is the distance a compound travels divided by the distance the solvent travels.
Would a compound with a high Rf value be near the top or near the bottom of a TLC plate?
A compound with a high Rf value would be near the top of a TLC plate.
Which separation technique uses an electric field?
Electrophoresis uses an electric field.
T/F, isoelectric focusing uses a gel with a pH gradient to separate proteins based on thier isoelectric points?
True.
SDS-polyacrylamide gel electrophoresis separates proteins based on what factor?
SDS-polyacrylamide gel electrophoresis separates proteins based on their masses.
T/F, agarose gel electrophoresis is used to separate fragments of nucleic acid?
True.
What type of spectroscopy is useful for identifying functional groups?
IR spectroscopy is useful for identifying functional groups. NMR has limited utility in this area.
Do symmetrical stretches exhibit an IR abosrption signal?
No, symmetrical stretches do no exhibit an IR absorption signal.
T/F NMR spectroscopy can be used to identify distinct ^1H protons in a molecule?
True.
Which purification technique involves a solid turning directly into a gas?
Sublimation occurs when a solid turns directly into a gas.
Which separation technique takes advantage of a solution containing two or more compounds with different boiling points?
Distillation separates based on different boiling points.
Which separation technique can be used to separate a mixture of particles with different densities and masses?
Centrifugation separates based on mass and density.
What separation technique makes use of two immiscible solvents?
Extraction makes use of two immiscible solvents.
What separation technique can be used to isolate a solid from a liquid?
Filtration can be used to isolate a solid from a liquid.
T/F, recrystallization is a process in which impure crystals are dissolved in hot solvent and then recrystallize as pure crystals as the solvent cools?
True.
How many different NMR peaks (doublets, triplets, etc.) would appear if the molecule being analyzed was Ethane?
1 singlet.
How many different NMR peaks (doublets, triplets, etc.) would appear if the molecule being analyzed was Propane?
1 septet (7) and 1 triplet.
How many different NMR peaks (doublets, triplets, etc.) would appear if the molecule being analyzed was 1,3-dichloropropane?
1 quintet (5) and 1 triplet.
How many different types of equivalent protons are there in 1-bromo-2-chloropropane?
There are 3 different types of equivalent protons in 1-bromo-2-chloropropane.
T/F, NMR can make use of both ^12C and ^13C?
False, ^12C has no magnetic moment and, therefore, cannot be used in NMR spectroscopy.
What type of spectroscopy is ideal for the study of conjugated olefins?
UV-vis spectroscopy is ideal for the study of conjugated olefins.
What type of spectroscopy can determine the molecular weight of a compound?
Mass spectroscopy determines the molecular weight of a compound?
What is the general formula for a carbohydrate?
Cn(H2O)m
T/F, monosaccharides undergo many of the same reactions as alcohols.
True.
What is the general formula for calculating the maximum number of possible stereoisomers of a molecule?
The general formula is 2^n where n=number of chiral centers.
A pyranose has how many members in its ring?
A pyranose has a six-member ring.
A furanose has how many memebers in its ring?
A furanose has a five-member ring.
T/F, when converting a Fischer Projection to a Haworth (ring) projection, groups on the right side of a Fischer Projection will be pointing upward?
False, groups on the right side of a Fischer Projection end up pointing downward in a Haworth Projection.
What monosaccharides make up a molecule of maltose?
Maltose is composed of two molecules of glucose.
Does cellulose contain β-1,4 glycosidic bonds or α-1,4 glycosidic bonds?
Cellulose contains β-1,4 glycosidic bonds.
Do starch and glycogen contain β-1,4 glycosidic bonds or α-1,4 glycosidic bonds?
Starch and glycogen contain α-1,4 glycosidic bonds.
What is mutarotation?
Mutarotation is the spontaneous change of configuration about C1 that occurs when monosaccharides are exposed to water.
T/F, glucose is an aldohexose?
True.
T/F, fructose is an aldopentose?
False, fructose is a ketohexose.
What is a reducing sugar?
A reducing sugar is any monosaccharide with a hemi-acetal ring.
T/F, the alpha carbon in chiral in all amino acids?
False, glycine’s alpha carbon has 2 hydrogens and is therefore not chiral.
What is a zwitterion?
A zwitterion is a species with both a positive and a negative charge.
Define amphorteric.
An amphoteric species can act as either a base or an acid.
In what direction will an amino acid with a neutral side chain move during electrophoresis at pH 4, if the pI of the amino acid is 7?
The amino acid will have a net positive charge and, therefore, move towards the cathode.
In what direction will an amino acid with a neutral side chain move during electrophoresis at pH 4, if the pI of the amino acid is 3?
The amino acid will have a net negative charge and, therefore, move towards the anode.
In what direction will an amino acid with a neutral side chain move during electrophoresis at pH 4, if the pI of the amino acid is 4?
The amino acid is at its isoelectric point and will not move.
T/F, the buffering capacity of an amino acid is greatest at its isoelectric point?
False, the buffering capacity of an amino acid is least at its isoelectric point. It is greatest at its two or more pKa’s.
Where are non-polar amino acids usually found in a protein and why?
Non-polar amino acids are usually found in the interior of a protein because they are hydrophobic.
Where are polar amino acids usually found in a protein?
Polar amino acids are usually found on the exterior of a protein.
What is the net charge of an acidic amino acid at physiological pH?
The net charge of an acidic amino acid at physiological pH is negative.
What is the net charge of a basic amino acid at physiological pH?
The net charge of a basic amino acid at physiological pH is positive.
What type of bond joins amino acids?
A peptide bond joins amino acids together.
Define the primary strucdture of a protein?
Primary structure refers to the sequence of amino acids.
Define secondary structure of a protein?
Secondary structure refers to hydrogen bond interactions within the protein.
What are the two most common types of secondary structure?
The two most common types of secondary structure are alpha-helix and beta-pleated sheet.
Define tertiary structure of a protein?
Tertiary structure refers to the three-dimensional folding of a protein.
What are the two pimary classifications (regarding tertiary stucture) of proteins?
Fibrous and globular proteins.
Define quarternary structure?
Quaternary structure only exists in proteins with more than one polypeptide subunit. It refers to the way the subunits arrange themselves.
What is a conjugated protein?
A conjugated protein is a protein that derives part of its function from a prosthetic group.
What happens when a protein denatures? What can cause a protein to denature?
A protein loses its three-dimensional shape with it denatures. Changes in temperature, pH, and solute concentration can cause denaturation.
Which type of alcohol (1º, 2º, 3º) can be oxidized to a carboxylic acid?
1º alcohols can be oxidized to carboxylic acids; however, 2º and 3º alcohols cannot.
What is a micelle? Is the interior hydrophobic or hydrophilic?
When placed in an aqueous solution, soap molecules arrange themselves into spherical structures called micelles. The soap molecules arrange themselves such that their polar heads face outward and their non-polar chains face inward.
Would you have to oxidize or reduce a carboxylic acid to prepare an alcholol?
Reduction of a carboxylic acid forms an alcohol.
T/F, acid chlorides are very reactive?
True.
How do electron donating groups affect the acidity of benzoic acid?
Electron donating groups reduces the acidity of benzoic acid.
How do electron withdrawing groups affect the acidity of benzoic acid?
Electron withdrawing groups increase the acidity of benzoic acid.
T/F, anhydrides react under the same conditions as acid chlorides?
True.
What is the product of the hydrolysis of an amide under acidic conditions?
The hydrolysis of an amide under acidic conditions will produce a carboxylic acid.
What are the products for the hydrolysis of an ester?
The products are a carboxylic acid and an alcohol.
What is the structure of a triacylglycerol?
3(OCOR)
What is saponification?
Saponification is the process whereby fats are hydrolyzed under basic conditions, to produce soaps.
T/F, a glycerol molecule attached to two carboxylic acids and one phosphoric acid is a phospholipid?
True.
Name CH₃CH₂NH₂
Ethylamine (common) or ethanamine (IUPAC).
Name CH₃CH₂CH₂CH₂N(CH₃)₂
N,N-dimethylbutylamine (common) or N,N-dimethylbutanamine (IUPAC).
How may alkyl groups are in a teriary (3º) amine?
A 3º amine has 3 alkyl groups attached to the nitrogen.
What is a quaternary ammonium compound?
A quaternary ammonium compound is a nitrogen atom attached to 4 alkyl groups. The nitrogen is positively-charged and, therefore, the compound exists as a salt.
T/F, an imine is a compound with a carbon-nitrogen double bond.
True.
Categorize R–(N-)–(N+)≡N
Azide.
Categorize RC≡N
Nitrile, cyanide.
Which types of amines can form hydrogen bonds (1º, 2º, 3º)?
1º and 2º amines can form hydrogen bonds.
