Organic Chemistry 3

amines

N with 3 things attatched to it and a lone pair, can H bond

can be 1, 2, 3, or 4

alkaloids

natural products containing a basic N atom

quaternary amines

4 alkyl groups with a positive charge, ammonium salt, chiral

mass spec of amines

off number of atoms, base peak at 30

IR spec of animes

1 and 2 at 3400

• 1 peak indicates secondary

• 2 peaks indicates primar

teritary does not absorb here

NMR of amines

N-H from 0.5-5, aromatic is more downfield, NH is not split

SP3 carbons to amines is 30-50

naming primary amines

name as substituent of parent chain, change -e to -amine

if not on the end of a chain, indicate with number

naming secondary or tertiary amines

if identical groups use di or tri

different groups name amine as ‘N-"‘ to indicate attatchement to R, put other groups in front, still use amine at the end, if another thing takes priority use amino-

aromatic amines

amino benzenes are named as anailine derivatives

N alkyl groups on amines

increasign e- density on N increases basicity

decresing e- density on N deceases basicity

electron donating groups increse electron density to increase basicity

aryl amine basicity

ressonance allows for e- delocalization, makes it less basic

alkyl substitutions on ring make it more basic due to less ressonance

e- donor groups reduce e- delocalizaiton, increases basicity

e- withdrawing groups increase e- delocalization, decreses basicity

amides and their basicity

carbonyl group with amine group on it

e- pair can be delocalized on the c=o with ressonance, decreases basicity becuse protonation would happen at the O not N

heterocyclic amine basicity

need to determine if N’s e- pair is part of aromatic pi system or not

if apart of system - cannot react without disrupting aromaticity, no basicity

if not apart of system - can interact and be basic

hybridization of animes on basicity

s character determines

sp2 orbitals are held tighter and have more s character so they are held tighter and are hard to react

sp3 is less s character so it is more basic

ketone and aldehydes to imines

uses alkyl amine or amine to make immine

reagents - Y-NH2

alkyl halides

uses ammonia, 1, 2, 3 amines to go to next level

ammonium salt intermediate

lone pair of nitrogen reacts with alkyl and halogen dissociates, makes intermediate, amine reacts again to H and pushes C-H bond e- to N

reagents - R-X

amine synthesis - example of nucleophilic substitution

1 or 2 amines with acid chloride to amine amide functional group

uses pyridine as base for HCl

replaces Cl with anime

reagents - acid chloride, pyridine

synthesis of substituted anilines

anilines cannot do freidal craft so a multistep process is needed

3 steps

1. protection of adding acid chloride to aniline, makes attatched to acid chloride without the Cl

2. friedal craft reaction with R-Cl and AlCl3 to add aklyll group as a o,p director

3. deprotonation with H3O+ and OH to take off carbonyl

reagents - carboxylic acid, R-Cl and AlCl3, and H3O+ and OH

Hoffman Elimination

converts amine to alkenen between alpha and beta carbon

can happen with 1, 2, 3 amines

uses methyl idodine

reagents - 1. CH3I, Ag2O, and heat

3 steps-

1. make good LG by forming quanternary ammonium salt

2. provide strong base

3. elimination to form double bond

major product will form on the less substituted C=C

cope elimination

3 amines are oxidized to amine-N-oxides with H2O2 or mCBPA

replaces lone pairs with oxygen

regents - H2O2 or mCPBA or ArCO3H

can then undergo elimination to form alkenes like hoffman

formation of diazonium salts with nitrous acid

uses strong acid and nirtrous acid- formed by NaNO2 to decompose to NO+

makes diazonium salt, N triple bond N

reagents - NaNO2, H-Cl

1. form the nitrosonium ion with HCl

2. diazotination to make triple bonded N

nitrousonium ion

electrophile that can react further

diazonium salt

N triple bond N

reacts a lot with things

aryl diazonium salt reacts with nucleophiles

salt to OH group on aryl ring

reagents - H2O

aryl salt to Cl or Br

puts Cl or Br on ring

reagents - CuCl or CuBr

aryl salt to cyanide group

adds C triple bond N

reagents - CuCN

aryl salts to F or I

regents - HBF4 or NaI or KI

aryl salt to H - remove functional group

helps to add when directors are in the way, can use salt as director and then remove it

reagents - H3PO4

aryl salt removing functional group example

aryldiazonium salts to azo compounds

electrophilic aromatic substitution reactions with activated arenes

needs strong aryl e- donating group

reagents - aryl with NR2 or OH

synthesis of amines - reductive animation

aldehydes and ketone to 1, 2, 3 amines

2 steps

1. nuc attatck of NH3 on C=O to form imine

2. reduction of imine to form amine

reagents - NH3, NaBH3CN

C=O gets replaced by C-N and C-H bonds

amine reduction of other functional groups

amines to amines uses LiAlH4 and H2O

goes from 1 to 1 amine, 2 to 2 amine, etc.

reagents - 1. LiAlH4 2. H2O

works for C triple bond N to 1 amine

nitro group to amine

R-NO2 to R-NH2

reagents - H2, Pd-C or Fe, HCl or Sn, HCl

gabriel synthesis of 1 amines

2 steps to use nuc to synthesize 1 amines

uses phthalimide and alkyl halide

reagents - phthalimide, H-X, OH, H2O

becomes to carboxyl anions on ring

carboxylic acids

RCOOH, c is sp2 hybridized

acyclic carboxylic acid nomentclature

long chain, change -e to -oic acid, acid will be in 1 postition

can use greek letters to indicate things as well

cyclic carboxylic acid nomentclature

name ring and add carboxylic acid, C1 on ring

common carboxylic acids

naming unsaturated acids with double bonds

remove -e form alkene, add -oic acid, start numbering at carbonyl group, use stereochemistry

naming di acids

on both ends of the chain, named with -dioic acid with parent name at the start

naming salts - carboxylate anions

cation and parent group + suffix (-ate)

properties of carboxylic acids

H bond donors and acceptors, have dimers, high bp and mp due to IMF’s, solublity similar to alcohols - more C’s is lower solubility (think hydrocarbon chains)

acid base chemistry of carboxylic acids

good acids due to resonance stabilized conj. base, favors generation of weaker acid, pKa around 5

carboxylic aid e- withdrawing groups

decrease pka and increases acidity

carboxylic acid e- donating groups

increase pka and decreases acidity