Organic synthesis Flashcards
What is the general formula for alkanes?
C_nH_(2n+2)
True or False: Alkenes are saturated hydrocarbons.
False
Fill in the blank: The process of converting an alkene to an alkane is called __________.
hydrogenation
What functional group characterizes alcohols?
Hydroxyl group (-OH)
Which reaction involves the substitution of a halogen in an alkane?
Free radical substitution
True or False: Carboxylic acids can act as both acids and bases.
True
What is the primary product when a carboxylic acid reacts with an alcohol?
Ester
Name the reaction type that forms an amide from a carboxylic acid.
Condensation reaction
What is the main reagent used for the reduction of aldehydes?
NABH4 (Sodium borohydride)
Which reagent is commonly used to oxidize primary alcohols to aldehydes?
Potassium dichromate (K2Cr2O7)
What is the key feature of a nucleophilic substitution reaction?
A nucleophile replaces a leaving group.
True or False: Benzene is a saturated compound.
False
What is the mechanism of electrophilic substitution in aromatic compounds?
The electrophile replaces a hydrogen atom on the benzene ring.
Fill in the blank: The product of a nitration reaction of benzene is __________.
Nitrobenzene
What is the role of sulfuric acid in the synthesis of esters?
Catalyst
Which type of reaction is used to form alkenes from alcohols?
Dehydration reaction
What is the effect of increasing the chain length on the boiling point of alkanes?
The boiling point increases.
True or False: Ethers can be hydrolyzed to form alcohols.
True
What is the primary use of thin-layer chromatography (TLC) in organic analysis?
To separate and identify compounds.
What does the retention factor (Rf) indicate in chromatography?
The distance traveled by the compound relative to the solvent front.
Fill in the blank: The process of breaking down a compound into simpler substances is called __________.
decomposition
What type of reaction occurs when an alkene reacts with a halogen?
Electrophilic addition
Name one method of preparing alkenes from alkanes.
Cracking
True or False: Primary alcohols can be oxidized to carboxylic acids.
True
What is the main product of the hydrolysis of esters?
Carboxylic acid and alcohol
What is the significance of using a reflux apparatus in organic synthesis?
To heat a reaction mixture without losing volatile components.
Which spectroscopy technique is used to determine the structure of organic compounds by measuring the vibrations of bonds?
Infrared spectroscopy (IR)
Fill in the blank: The process of heating a compound with a strong acid to break it down is called __________.
acid hydrolysis
What type of isomerism is exhibited by alkenes?
Geometric (cis-trans) isomerism
True or False: All alcohols can form hydrogen bonds.
True
What is the role of a drying agent in organic synthesis?
To remove water from organic solvents.
Name the type of reaction where two molecules combine to form a larger molecule with the loss of a small molecule.
Condensation reaction
What is the common name for ethanoic acid?
Acetic acid
Fill in the blank: The reaction of an acid and a base to form a salt and water is called __________.
neutralization
What type of chemical reaction occurs when a compound loses electrons?
Oxidation
What is the main characteristic of a primary amine?
One alkyl group attached to the nitrogen atom.
True or False: Aromatic compounds are more reactive than aliphatic compounds.
False
What is the purpose of recrystallization in organic chemistry?
To purify solid compounds.
What is needed to turn nitrobenzene into phenylamine?
Reduction using Sn and concentrated HCl.
How do you convert ethene into ethanoic acid?
Add H2SO4 with water and reflux with acidified potassium dichromate.
What reagents are needed to convert benzene into 1-phenylpropanone?
Friedel-Crafts acylation using propanoyl chloride and AlCl3.
What must be thoroughly investigated before commercial production of a compound?
Effectiveness, safety, side effects, and so on.
What is the first step in working out a synthesis scheme?
Write down the formula of the starting molecule (A) and the target molecule (X).
List the functional groups you should know for organic synthesis.
- Alkanes
- Alkenes
- Halogenoalkanes
- Alcohols
- Amines
- Aldehydes
- Ketones
- Acid derivatives
- Arenes
What does ‘yield’ measure in organic synthesis?
The efficiency of the conversion of a starting material into a product.
Why is it important to keep the number of steps in a synthesis scheme small?
To maximise the yield of the target.
Fill in the blank: The reaction of cyanide ions with a __________ will be needed if the target molecule has one more carbon atom than the starting material.
halogenoalkane
How do you convert propanone into 2-bromopropane?
Reduce with NaBH4 to to propan-2-ol and then react with KBr/H2SO4
What potential does the target compound have after synthesis?
Potential for use in reactions and processes.
What is the significance of atom economy in organic synthesis?
It relates to the efficiency of the conversion process.
How do you convert cyclohexanol into cyclohexene?
Dehydrate with P2O5
How do you turn but-1-ene into butanone?
Conc. sulphuric acid with water and then oxidise with acidified potassium dichromate
What do you need to turn ethanoic acid into methyl ethanoate?
Methanol with an acid catalyst
What reagent do you need to make but-1-ene into butan-2-ol?
Conc. sulphuric acid with water
What should you react 1-bromobutane with to get pentanenitrile?
Potassium cyanide
What is the role of hydrogen and nickel in turning a nitrile into an amine?
Hydrogen reduces the nitrile and nickel acts as a catalyst
Fill in the blank: Secondary alcohols are oxidised to _______.
ketones
This is part of the oxidation process in organic chemistry.
What oxidising agent is used to oxidise primary alcohols to aldehydes?
Potassium dichromate (VI)
It is acidified with dilute sulfuric acid for this reaction.
What is the outcome of oxidising aldehydes?
Carboxylic acids
Aldehydes can be further oxidised to form carboxylic acids.
What should you be able to recall regarding functional groups?
Reactions and conditions such as heating, refluxing, acidic or alkaline conditions, and catalysts
Understanding these aspects is crucial for organic synthesis.
True or False: Propylamine can be made from ethene.
True
Ethene can be made into a haloalkane and then reacted with KCN
What is the significance of the inter-relationships between functional groups?
They help in revising knowledge of organic reactions
Understanding these relationships is key to successful synthesis.
What is a common method to produce a library of aldehydes from alcohols?
Oxidising several alcohols of different chain lengths
This method allows for the exploration of various compounds’ medicinal potential.
Fill in the blank: The reaction of cyanide is an example of a reaction that may involve _______.
functional groups
This highlights the importance of functional groups in synthetic reactions.
