Organic Chemistry
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Richards
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Introduction
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Retrosynthetic Analysis
Control
Absolute / Relative
Weinreb Amide
Latent Polarity
Oxidation Level
Functional Group Interconversion
(alkyle  methyl ketone (HgO /
H2SO4)
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Synthesis of Rings
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Reduction
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Carbonyl to alcohol (NaBH4 LiAlH4)
Carboxylic acid to alcohol (BH3)
Amide to amine (BH3)
Reductive amination (Na(CN)BH3)
Partial Reduction of ester to aldehyde
(DIBAL or LiAlH4 then partial oxidation
using PCC or TPAP/NMO)
Nitrile to aldehyde (DIBAL)
Oxidation
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Alcohol to Aldehyde (PCC or
TPAP/NMO)
Alcohol to Carbonyl (Dess-Martin
Periodinane DM)
Alcohol to ketone (Na2Cr2O7)
Alcohol to carboxylic acid (KMnO4)
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Dihydroxylation (OsO4 / NMO)
Epoxidation (m-CPBA)
Ozonolysis (O3 then Me2S (aldehyde),
H2O2 (carboxylic acid), NaBH4
(alcohol))
Protecting Groups
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Introduction
Aldehydes / Ketones (Acetal –
(HO(CH2)2OH) on , acid off)
Diol (Acetal – aldehyde on, acid off)
Carbonyl (dithane HS(CH2)3SH on, BuLi
/ Hg2+ off)
Diels Alder reaction
1,6-dicarbonyls from
cyclohexenes (ozonolysis)
Hetero-Diels Alder and 5
membered rings
Stereo specificity and Stereo
selectivity
Endo / Exo
Baldwin Rules
Carbonyl Chemistry
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Alkene Oxidations
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Alcohol (trialkylsilylchloride /
imidazole on, TBAF off)
Phenol (NaH / MeI on, HBr off)
Nitrogen (amide – harsh conditions)
Nitrogen (BOC on, TFA off)
Deprotection by hydrogenation
(cleavage of R-OH or R-NH bond with
hydrogen – only practical for benzyl
group) (H2 / Pd / C)
Deprotection by hydrogenation of
carboxybenzyl group CBz
Basic
Addition to carbonyl group containing
adjacent stereo genic centre (felkin
anh model)
Curtin Hammett principle
Chelation control
Stereoselective aldol reactions
Ways to control enolate geometry
o Cyclic enolate precursor
o Boron enolates
Alkenes
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Reduction of alkyne gives CIS alkenes
Wittig reaction
Destabilised ylids CIS
Stabilised ylids TRANS
Horner-Wadsworth Emmons
Metathesis
Asymmetric Synthesis
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Types of chirality
Catin-Ingolg-Prelog rules
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Simple calculations
o Number of stereoisomers = 2n
o Enantiomeric excess
o Specific rotation
o Optical purity
Chiral Pool
Resolution
Resolving agents
Auxiliaries
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Chiral auxiliaries
Dave Evans Auxiliaries
o Diels Alder
o Aldol
Asymmetric Catalysis
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Chiral catalysts vs auxillaries
Addition of XY to prochiral ketone
Oxazaborolidene
Asymmetric oxidation (OsO4)
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Page
Organosulfur
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Bew
Click Chemistry
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Advantages
Resonance of N3
Copper
Ruthenium
Mechanism
Tetrapeptide analogs
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Multicomponent Reactions
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Advantages
Strecker Synthesis
Free radical mediated
Organoboron
Resonance of isocyanide
Passerini
Ugi
Stevenson
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Heck
Stille (tin)
Suzuki (boron)
Sonogashira (copper)
Negishi-Kumada (grinyard)
Buchwald-Hartig
Formation of Pd(0)
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Introduction
Sulfide formation
o Harpps’ reagent
Sulfide reactions
o Stevens & sommelet
rearrangements
Sulfoxide formation
o Allylic sulfoxide – sulfenic
ester rearrangement
Sulfoxide reactions
o Pummerer rearrangement
o Intramolecular pummerer
o Syn-elimination of sulfenic
acid
Use as reagents
o Kornblum oxidation
o Swern oxidation
Sulfone reactions
o Julia reaction
 Heteroaryl sulfones
 Alkyl halides
o Ramberg-Backlund reaction
o Cheloptropic elimination of
SO2
Sulfur Ylids
o Simple
o Oxosulfonium
o Epoxides from carbonyl
groups
o Reactions with enones
o Trost reagents
Thioketones
o Corey-Winter
Organosilicon
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o
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Introduction
Chemistry
Sila-pummerer
Peterson
Vinyl silanes
Electrophilic substitution
o
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Allyl silanes
Reactions with electrophiles
Silyl enol ethers
 Ireland-Claisen
 Ozonolysis
 Epoxidation
 Oxidation to enone
 Hydroboration
 Alkylation
 Conjugate addition
 Mukaiymama
 Orthoesters
OrganoSelenium
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Introducton of Se
Selenoxide elimination
Selinium ion cyclization
Selenium dioxide#
Organophosphorus
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Mitsunobu
Corey-Fuchs
Seyferth Gilbert
Bestmann modification