Module 6: Amine, Chirality, Amino Acid, Nitriles, Amide Flashcards
Amines
What is an amine
Organic compound derived from ammonia in which one or more h atoms has been replaced by a carbon chain or ring
Amines
What is the nitrogen attached to in an aliphatic amine
Atleast one alkyl group
Amines
What is the nitrogen attached to in an aromatic amine
Directly attached to Aromatic ring
Amines
What are they classifies into
Primary secondary tertiary
Amines
Is ammonia an amine
No
Amines
General structure for primary
R-NH2
Amines
General structure for secondary
R-NH-R’
Amines
What is general structure for tertiary
R-NR’-R’’
Amines
How do you name primary amine where amine group on end of chain
Alkylamine
Amines
How do you name a primary amine where amine in middle of carbon chai.
2-aminealkane
Amines
How do you name a secondary or tertiary
N-alkyl-N-alkylamine etc
Amines
What can they act as
Bases and nucleophiles
Amines
Why can they act as bases
Can accept protons (lone pair on N)
Amines
What effect do the R groups have
Inducing effect as push electrons towards N atom
Amines
Which classification of amines are the strongest base and why
Has more inducing effect
Amines
What is the weakest base and why
Phenylamine amine as lone pair is partially delocalised so pulled away so less available to accept proton
Amines
What bond is formed when an amine accepts a proton
Dative covalent bond
Amines
What is produced in reaction with acid
Alkylammonium salt
Preparation of Amines
What is the single step method to pepare an primary amine
Nucleophilic substitution with ammonia
Preparation of Amines
What are the conditions for nucleophilic substitution with haloalkane
Excess Ethanoic ammonia, reflux
Preparation of Amines
What is produced in reaction haloalkane and excess ammonia
Primary amine + ammonium salt
Preparation of Amines
Mechanism
Need to know *
Preparation of Amines
Equation for reaction between chloroethane and NH3
CH3CH2Cl + NH3 —> CH3CH2NH2 + NH4+Cl-
Preparation of Amines
Why is ethanol used as solvent
To prevent substitution of the haloalkane by water to produce alcohols
Preparation of Amines
Why is excess ammonia used
Reduce further substitution of the amine group to form secondary and tertiary amines
Preparation of Amines
What can the primary amine formed now act as
A nucleophile to the haloalkane
Preparation of Amines
What does primary amine + halo alkane produce
Secondary amine + HCl
Preparation of Amines
How could a tertiary amine then be formed
Haloalkane + secondary amine
Preparation of Amines
What is the two step preparation
Nucleophilic substitution between halo alkane and cyanide ion
Reduction of nitrile
Preparation of Amines
Reagents and conditions for halo alkane and cyanide
NaCN in ethanol , reflux
Preparation of Amines
Reaction between bromoethane and CN-
CH3CH2Br + CN- —> CH3CH2CN + BR-
Preparation of Amines
What is key in adding a cyanide group
Carbon chain is extended
Preparation of Amines
Why is there high electron density in CN
Unsaturated bond with electrons which are localised
Preparation of Amines
Reagent or condition for nitrile to amine
2 H2, Ni catalyst /
6[H]
Preparation of Amines
What types or reaction is nitirle to amine
Reduction.
Electrophilic addition
Hydrogenation
Preparation of Amines
Why might the 1 step method be preferred
Less energy required as only one step
Preparation of Amines
Why may the 2 step method be proffered
Further substitution doesnt occur
Preparation of phenyl amine
How many steps required from benzene
2
Preparation of phenyl amine
Why can’t ammonia just be used
Ammonia is a nucleophiles whereas benzene undergoes reactions with electrophiles
Preparation of phenyl amine
Conditions for benzene to nitrobenzene
Conc H2SO4
conc HNO3
50’C
Preparation of phenyl amine
Type or reaction for benzene to nitrobenzene
Electrophilic substitution
Preparation of phenyl amine
Conditions and reagent for nitrobenzene to phenyl amine
Tin, conc HCl, reflux
Then NaOH(aq)
Preparation of phenyl amine
What type of reaction is nitrobenzene to phenyamine
Reduction
Preparation of phenyl amine
Equation for nitrobenzene to Phenylamine
C6H5NO2 + 6[H] —> C6H5NH2 + 2 H2O
Chirality
What type of isomerism are optical isomers
Stereoisomerism
Chirality
Deifntion for optical isomers (3)
Molecule which contains a chiral centre and has non superimposable mirror images where each one rotates a plane of polarised light in opposite directions
Chirality
When does optical isomerism occur
When there is a chiral centre
Chirality
When is there a chiral carbon
Asymmetric carbon atom with four different groups and no double bond
Chirality
How do you draw two optical isomers
Draw molecule in 3D plane
Draw mirror line
Draw reflected 3D molecule
Chirality
What are optical isomers also known as
Enantiomers
Amino acids
What would functional groups do they contain
Amine and carboxylic acid
Amino acids
When is an amino acid alpha
When both functional groups and a H atom are attached to the same group
Amino acids
What is the general formula for an alpha amino acid
RCH(NH2)COOH
Amino acids
What two properties do they have
Acidic and basic properties
Amino acids
What is a zw itter ion
When proton from COOH groups is donated to NH2 to form a dipolar ion
Amino acids
What is the isoelectric point
Specific pH are you which the zwitter ion is formed from amino acid
Amino acids
What state are they in neutral ph
Basic non charged compound
Amino acids
What happens at Isoelectric point
Zwitter ion formed with Positve NH3 and negative COO-
Amino acids
What happens at a ph higher then the isoelectric point
The NH2 group stays neutral but COO- has charge
Amino acids what happens at ph lower then the islelectric point
COOH group stays neutral whereas the NH3+ has charge
Amino acids
What type of isomer can they form
Optical isomers
Amino acids
Why do they form optical isomers
Have a chiral carbon with four different groups -COOH, -NH2, -R, -R’(H)
Amino acids
How many optical isomers are formed
Two
Amino acids
Which amino acid has no optical isomerism and why
Glycine as had two H atoms
Amino acids
How are zwitter ions formed
Proton from COOH groups moves to NH2
Amino acids
Why do zwitter ions have higher melting and boiling points
Produces increased intermolecular forces due to charge
Amino acids
Why are amino acids bifunctional
Have two functional groups one which can act as a base and one which can act as acid
Amino acids
Which funtion al group an act as a base
NH2
Amino acids
Which functional group can act as an acid
COOH
Amino acids
Equation for reaction with H+
HOOCCH(R)NH2 + H+ —> HOOCCH(R)NH3+
Amino acids
Equation for reaction with HCl
HOOCCH(R)NH2 + HCl —> HOOCCH(R)NH3+Cl-
Amino acids
Equation for reaction with OH-
HOOCCH(R)NH2 + OH- —> -OOCCH(R)NH2 + H2O
Amino acids
Equation for reaction with NaOH
HOOCCH(R)NH2 + NaOh —> Na+ -OOCCH(R)NH2 + H2O
Reactions of Amino acids
What do you have to be careful of with reactions
That R chain wont also react with it
Reactions of Amino acids
What is formed when reacted with NaOH
Salt + water
COO-Na+
Reactions of Amino acids
What is formed when reacted with HCl
Salt
NH3+Cl-
Reactions of Amino acids
What happens when reacted with alcohol and what conditions needed
Esterification
Conc H2SO4
Reactions of Amino acids
What is produced when reacted with alcohol with conc H2SO4
Ester + water
C(=O)OC
Reactions of Amino acids
What happens when reacted with another amino acid
Form a condensation polymer
Reactions of Amino acid
What formed when reaction wih Acyl chloride
Amide bond + HCl
NH-C(=O)C
Amides
What funtional group do they have
-CONH2
Amides
Why do they behave differently from amines
Carbonyl group pulls electrons away from rest of -CONH2 group
Amides
How can they be classified
Primary or secondary depending on how many hydrogens the nitrogen atom is bonded to
Preparation of Amides
How can they be formed from carbonxykic acid and what if formed equation
Carboxylic acid + amine —> amide + water
Preparation of Amides
What type of reaction is carboxylic acid + amine
Condensation
Preparation of Amides
How can they be prepared from acid anhydride equation
Acid anhydrides + ammonia —> amide + carboxylic acid
Preparation of Amides
How can they be prepared from Acyl chlorides equation
Acyl chloride + amine —> amide + HCl/NH4Cl
Reactions of Amides
What does it undergo
Hydrolysis
Reactions of Amides
What is hydrolysis
Splitting a compound using water
Reactions of Amides
What two types of hydrolysis do they undergo
Acidic
Alkaline
Reactions of Amides
What is needed for acidic hydrolysis
Heating with dilute acid
Reactions of Amides
Reactions of Amides
What is formed in acidic hydrolysis
Carboxylic acid and ammonium salt
Reactions of Amides
Equation for N-ethylpropanamide with HCL
CH3CH2CONHCH2CH3 + HCl(aq) —H2O—> CH3CH2COOH + CH3CH2NH3Cl
Reactions of Amides
What is needed for alkaline hydrolysis
Heat with sodium hydroxide
Reactions of Amides
What is formed in the alkaline hydrolisis
Carboxylate salt and amine
Reactions of Amides
Reactions of Amides
Equation for N-ethylethanamide and NaOH
CH3CH2CONHCH2CH3 + H2O —NaOH(aq) —> CH3CH2COO-Na+ + CH3CH2NH2
polymers
What are the two p types of polymers
Addition
Condensation polymers
polymers
What are addition polymers a and how are the formed
Long chain molecules made from joining together many shorter molecules(monomers) together to form a long chain molecule
polymers
What are the monomers for addition polymers
Alkenes or moleucles with C=C bonds
polymers
Why are addition polymers bad for they environment
Non biodegradable due to absence of polar bonds in the main chain (all C-C bonds)
polymers
What is atom economy like for addition polymers
100%
polymers
What are condensation polymers and how are they formed
Long chain molecules made from joining together many shorter molecules (monomers ) together to form a long chain molecule with water also formed
Condensation polymers
What are the monomers
Di carboxylic acids a with diols
Di carboxylic acids with diamines
Amino acids
Compound containing an amine and carboxylic acid functional group
Condensation polymers
Two examples
Polyesters
Polyamides
Condensation polymers
Wat is a polyamide
When Di carboxylic acid reacts with Di amine polyamide formed and water released
Condensation polymers
How do you show one repeating unit
Open bonds at either end (…—…)
Condensation polymers
How do you show the polymer structure
Square brackets with bond at either end with one repeating unit
N at end to show large number
Condensation polymers
What is a polyester
When Di carboxylic acid react with a diol forms poly ester and water is released
Hydrolysis of condensation polymers
What is hydrolysis
Splitting a compound using water
Hydrolysis of condensation polymers
What conditions can cause hydrolysis of polyesters and polyamides
Aqueous acid/ aqueous alkali
Hydrolysis of condensation polymers
What is formed in the acid hydrolysis of a polysester
Carboxylic acid and alcohol
Hydrolysis of condensation polymers
What is formed in the alkaline hydrolysis of a polyester using NaOH
Sodium carboxylate salt
Hydrolysis of condensation polymers
What is formed in the acid hydrolysis of a polyamide
Carboxylic acid and ammonium salt
Hydrolysis of condensation polymers
What is formed in the alkaline hydrolysis of a polyamide using NaOH
Sodium carboxylate salt and amine