Oxidation of alcohols 1 1 2 1 1

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Oxidation of alcohols 1+ 1 - 2 - 1+ 1+ 1 o alcohol 1+

Oxidation of alcohols 1+ 1 - 2 - 1+ 1+ 1 o alcohol 1+ 2 - 3+ 1+ aldehyde 2 - 2 - 1+ carboxylic acid [O] = oxidizing agent dichromate permanganate Cr 2 O 72 - Cr 3+ Mn. O 4 - oxidation = loss of e- density from C 1. binding O 2. removing H

Alcohols oxidation of alcohols: [O] = Cr 2 O 72 - or Mn. O

Alcohols oxidation of alcohols: [O] = Cr 2 O 72 - or Mn. O 421 o alcohols [O] aldehyde [O] carboxylic acid [O] + Cr 3+ + Cr 2 O 72 methanol [O] methanal formaldehyde methanoic acid formic acid

Alcohols oxidation of alcohols: [O] = Cr 2 O 72 - or Mn. O

Alcohols oxidation of alcohols: [O] = Cr 2 O 72 - or Mn. O 422 o alcohols [O] ketone [O] no reaction

Alcohols oxidation of alcohols: [O] = Cr 2 O 72 - or Mn. O

Alcohols oxidation of alcohols: [O] = Cr 2 O 72 - or Mn. O 423 o alcohols [O] no reaction

Alcohols Condensation Reaction CH 3 – OH + HO – CH 3 H 2

Alcohols Condensation Reaction CH 3 – OH + HO – CH 3 H 2 SO 4 CH 3 – O – CH 3 + H 2 O two molecules combine to form larger molecule + water alcohol + alcohol ether + H 2 O

Ethers R water alcohol ether H-bond acceptor O no H-bond donor dipole-dipole interactions low

Ethers R water alcohol ether H-bond acceptor O no H-bond donor dipole-dipole interactions low b. p. soluble in polar solvents

Ethers Common nomenclature : name both R groups + ether 1 2 1 3

Ethers Common nomenclature : name both R groups + ether 1 2 1 3 O. . propyl methyl propyl ether methyl dimethyl ether methyl “ether” bunny propyl people ether

Ethers Reactions Formation: H 2 SO 4 condensation reaction Peroxide formation: peroxide

Ethers Reactions Formation: H 2 SO 4 condensation reaction Peroxide formation: peroxide

Aldehydes and Ketones 120 o aldehyde C=O carbonyl group C and O are sp

Aldehydes and Ketones 120 o aldehyde C=O carbonyl group C and O are sp 2 hybridized ketone

Aldehydes and Ketones Nomenclature 1. Longest chain with C=O is parent 2. Suffix is

Aldehydes and Ketones Nomenclature 1. Longest chain with C=O is parent 2. Suffix is “-al” or “-one” 3. C 1 is always C=O in aldehydes In ketones, C=O is given lowest number 4. C=O has precedence over -OH (called “hydroxy”)

3 4 5 4 2 3 2 2 -bromo-3 -methylbutanal 1 2 3 1

3 4 5 4 2 3 2 2 -bromo-3 -methylbutanal 1 2 3 1 1 3 - pentanone trans 3 -hydroxy-2 -methyl cyclobutanone

Physical properties H H polar . . C O. . + H H +

Physical properties H H polar . . C O. . + H H + -. . C O. . : higher b. p. than alkanes H-bond acceptor soluble in polar solvents no H-bond donor lower b. p. than alcohols

Reactions Reduction [R] = reducing agent [R] 4 3 1 2 CH 3 -

Reactions Reduction [R] = reducing agent [R] 4 3 1 2 CH 3 - CH 2 - CHO butanal [R] 1 3 2 Li. Al. H 4 Na. BH 4 H 2/Pt 4 2 - butanone CH 3 - CH 2 -OH