environmental organic chemistry (chem 331) org chem intro 2018.pdf · environmental organic...
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ENVIRONMENTAL ORGANIC CHEMISTRY
CHEM 331
Where do organic contaminants go?
How long will they remain?
What happens to them?
Portable ‘hydrolyzer’ lab to guzzle Syria's sarin stockpile
D. MacKenzie, New Scientist, October 11, 2013
Neonicotinoids Implicated in Bee Colony Collapse Banned by EU
DDT and
PCBs
Distribution and Fate in the Environment
PHYSICAL PROCESSES
• Partitioning (Equilibrium Constants)
• air-water, Kaw (aka KH)
• octanol-water, Kow
• organic matter-water, Kom (and Kd)
• Vapour Pressure, Po
• Water Solubility, Cwsat
Depend on Physical Properties of Molecules
Inter and Intra Molecular Forces
Functional Groups and Substitutents:
STRUCTURE – ACTIVITY RELATIONSHIPS
CHEMICAL PROCESSES
• Nucleophilic Substitution (eg. Nu=H2O, Hydrolysis)• Acid/base• Oxidation• Reduction • Photochemistry
Functional groups: affect chemical products
Substituents: affect thermodynamics and kinetics
STRUCTURE – REACTIVITY RELATIONSHIPS
Factors that Affect Thermodynamics and Kinetics of Organic Reactions
• Quantifying Steric and Electronic Effects
REACTION MECHANISMS
SN1, SN2, E1, E2, Ecb1,
EAS, NAS, A1, A2, B1, B2
CLASSES of ENVIRONMENTALLY RELEVANT ORGANIC MOLECULES
Class Examples
Haloalkanes CFC’s, lindane
Haloaromatics PCB’s, dioxins
PAHs benzo[a]pyrene
Phthalates dipropyl phthalate
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Br
BrCl
F
Cl
DBCPlindaneCFC-122
Cl
Cl
O
O
Cl
Cl Cl
Cl
Arochlor-1212 2,3,7,8-TCDD
O
O
O
O
Examples of Common InsecticidesCl Cl
Cl
Cl Cl
N
N
N
Cl
N
H
N
H
O
Cl
Cl
Cl
Cl
Cl Cl
O
O
O
N
H
CH3CH2OP
S
O
OCH2CH3
N
N
Cl
HN
O
N
ClCl
Cl
Cl
Cl
Cl
Cl
O
ClCl
OH
O
O
NO2
O2N
O
NCl
Cl Cl
O P O
S
O
OP
O
O
O
NO2
DDT Atrazine
Dieldrin
2,4-D
2,4-Dinitrophenylacetate
Chlorpyifos Parathion
Diazinon HeptachlorMonuron
Carbofuran
Examples of Common Surfactants
R S O Na
O
O
R = C1 0 t o C1 3
R = C1 0 t o C1 6
R CH2COO Na S O Na
O
OR2
R1
R1 , R2 = C1 1 t o C1 7R = C1 1 t o C1 7
S O Na
O
O
R CH2 O
R2
N
R4
R3R1
Cl R1 = R2 = C1
R3 = R4 = C16 to C18
O (CH2CH2O)nHCH2R
R = C7 t o C1 7 n = 3 t o 15
R O (CH2CH2O)nH
R = C8 t o C1 2 n = 5 t o 10
Alkylphenol polyethyleneglycol Fatty alcohol polyethyleneglycol ethers
(APEO) (FAEO)
Quaternary ammonium chloride (QAC)
Soaps Linear alkylbenzene sulfonates Secondary alkylsulfonates Fatty alcohol sulfates
(LAS) (SAS) (alkyl sulfates, FAS)
Toxicological Mechanism – Organophosphate
pesticide (Chlorpyrifos)
Metabolism
Adduct formation
‘Aging’
N
Cl
ClCl
PO
O
S
O
NH CH C
H2C
O
...FGE AGAAS...
N
Cl
ClCl
PO
O
O
H3C
H3C
O
P
O O
O
CH3
H3C
O
HN CH C
CH2
O
AGAAS...
P
HOO
O
CH3
O"Aging"
Chlorpyrifos 0xon
Chlorpyrifos
H3C
H3C
CYP450
Dealkylation
NH CH C
H2C
O
...FGE AGAAS...
OH
...FGE
+
Dr. Chris Simpson, Associate Professor, Department of Environmental and
Occupational Health Sciences, University of Washington, Seattle, WA USA
substitution
Hydrolysis/substitution
substitution
Chemical Structures of OP Adducts
HN CH C
H2C
O
FGE AGAAS
P
O O
O
CH3
H3C
O
HN CH C
H2C
O
FGE AGAAS
P
O O
O
CH3
H3C
O
HN CH C
H2C
O
FGE AGAAS
P
O OH
O
H3C
O
HN CH C
H2C
O
FGE AGAAS
P
O OH
O
H3C
O
Dimethyl adductDiethyl adduct
Aged methyl adductAged ethyl adduct
Poster Assignment 2018Perfluorooctanoic Acids
Naphthenic Acids
Triazine pesticides
Nonyl phenols
Chlorinated alkanes/alkenes
N-nitrosoamines
Neonictinoids
Phthalates
Parabens
Benzophenone sunscreens
Polychlorinated biphenyls
Polychlorinated dibenzodioxins/furans
Organophosphate esters
Carbamate pesticides
Transport and Fate of Emerging
Class of Environmental Contaminants