Chapters 20 and 24
No description yet. This curated deck is ready for daily study.
Card preview (24)
Describe how primary amines are named
Root name is based on the longest chain with the NH2 Number so the amine has the lowest possible number Add -amine suffix
Describe how secondary amines are named differently than primary amines
The other alkyl group is treated as a substituent, with an N locant and is listed before numerical locant N-propylamine
Describe how tertiary amines are named differently than primary amines
The other alkyl groups are treated as substituents with N as the locant and are listed before numerical locants N-ethyl-N-methylpropanamine
What is the structure of aniline?
Benzenamine, phenylamine, amino benzene NH2 directly attached to benzene ring
What is the structure of p-toluidine?
4-methylbenzylamine NH2 and CH3 on benzene ring, directly across from each other
What is the structure of imidazole?
Five carbon ring, NH on top peak, N on bottom, double bonds on sides
What is the structure of pyrrole?
Five carbon ring, NH on top peak, double bonds on sides
How is amine basicity connected to the charge on nitrogen?
Increases with higher negative charge conjugate base is always more basic
How is amine basicity connected to conjugation?
Conjugated amines are worse bases Resonance in conjugate base to distribute the negative charge from donating
How is amine basicity connected to inductive effects?
Inductive effects decrease basicity Remove electron density from conjugate base, stabilizing it
How is amine basicity connected to pi-donating or pi-accepting?
Basicity decreases when acting as a pi-donor Significant resonance form where lone pairs on nitrogen form new pi-bond with carbon Basicity is decreased when attached to pi-acceptor or meta director (as in inductive effects)
How is amine basicity connected to hybridization?
Lone pairs on SP hybridized nitrogens are the least basic, those on SP3 are the most basic
How does amine basicity compare to amide basicity?
Amides are far less basic Lots of resonance stabilization in conjugate base
How do you make amines from ammonia? How do you control the substitution?
RX + NH3 → RNH2 Add excess RX for increased substitution
How do you make amines from NaN3? What are the two things it can react with initially? What is the intermediate? What are the four things it can then react with?
RX (or acid chloride) + NaN3 → RN3 + Na/EtOH (or LiAlH4 or H2/Ni or NaBH4) → RNH2
How can you convert a nitro group to an amine? What two things can it react with?
RNO2 + LiAlH4 (or H2/Ni) → RNH2
How can you convert an amide to an amine? Give the two methods and all possible reactants. (ignore named reactions)
Amide + LiAlH4 (or H2/Ni) → RNH2 Replaces the =O with hydrogens OR Amide + Very Strong Acid/Base → R2NH
Describe the two-step process of the first stage of Gabriel synthesis
Phthalimide + KOH + RX → Phtalimide with R instead of H, called an N-substituted phthalimide
Describe the two options for the second stage of Gabriel synthesis
N-sutstituted phalimide + NH2NH2 and EtOH/heat → RNH2 N-substituted phalimide + (1)H+/H2O/heat + (2)OH- → RNH2
How can you create amines from nitriles (CN)? What are the two options for reactants?
RX + NaCN → RCN + (1) LiAlH4/ether (or H2/Ni) + (2) H2O → primary amine
How can you create amines from aldehydes and ketones?
Add NH3 (1), RNH2 (2) or R2NH (3*) and source of H (such as NaBH4) Replaces the =O with hydrogen and the reactant
Describe the Hoffman Rearrangement
Amide + (1) Br2/NaOH + (2) H2O → RNH2 R is from the other group attached to =O (Nh2 is the other one) Remove =O and single bond other groups to each other
Describe the Curtius Rearrangement
Acid Chloride + (1) NaN3 + (2) heat + (3) H2O → RNH2
Amine + Formaldehyde → ? + (1)H+ (2)NaBH3CN → ?
Imine, RN(H)CH3 (replace an H with CH3)