Organic Chemistry 3 Flashcards
Jones’s oxidation
Treatment of phenols with oxidizing reagents produces compounds called quinones
Oxidation of primary alcohol by PCC
PCC (pyridinium chlorochromate, C5H6NCrO3Cl) is a “ mild” (anhydrous) oxidant, which means it only partially oxidizes primary alcohols
It stops after the primary alcohol has been converted to an aldehyde because PCC lacks the water necessary to hydrate the aldehyde (aldehydes are easily hydrated).
When aldehydes are hydrated (geminal diols or 1,1-diols), they can be oxidized to carboxylic acids.
PCC will also form ketones from 2° alcohols, so the only difference between PCC and all of the other oxidizing agents is how they react with 1° alcohols.
Tertiary alcohols are already as oxidized as they can be and so do not react with any of the oxidizing agents.
Conversion of Alcohol to Alkyl Halide (SN2)
Conversion of Alcohol to Alkyl Halide (Sn1)
Compare and contrast 2 popular reducing agents
(LiAlH4 and NaBH4)
LAH is the powerful one, and it will reduce just about anything (even esters, amides, and carboxylic acids) all the way to an alcohol.
NaBH4 is weaker, so although it, too, will reduce aldehydes, ketones, or acyl chlorides, it cannot reduce esters, carboxylic acids, or amides.
Williamson Ether Synthesis (basic)
The alkoxides behave as nucleophiles and displace the halide or tosylate via an SN2 reaction, producing an ether.
Note that it is in competition with E2.
Williamson Ether Synthesis with Phenol
internal SN2 displacement.
Michael Addition
Hemiacetal Formation
Acetal and Ketal Formation
Wittig Reaction (Step 1)
Wittig Reaction (Step 2)
Aldehyde Oxidation (KMnO4)
Pretty much any oxidizing agent (except PCC) can oxidize aldehydes into carboxylic acids; some examples are KMnO4, CrO3, Ag2O, and H2O
Ketone Reduction