Chem 116 Presentation

Exploration of a Selective Aerobic

Oxygenation Reaction

William GuyStahl Lab

Background Selective Oxidation with O2

Green, Abundant, Inexpensive

Uncontrolled Oxidation: Combustion

Goal is to find ways to control reactivity of O2

Controlled with catalysts

Electron Withdrawing Group

SelectivityControl of reactivity of O2

~88 kcal/mol~104 kcal/mol

~88 kcal/mol

NHPI (n-hydroxylphthalimide)

~100 kcal/mol

Ethylbenzene

Fox,T.;Kollman,P. C-H Bond Dissociation Energies in Toluene, 1996 100, 2950-2956Lao,Yu-Ran; Handbook of Bond Dissociation Energies, 2003, 3.1,3.4

NHPI PINO

Studied Reaction Selective NHPI-mediated aerobic oxidation of ethylbenzene was

explored

A series of activators was screenedeg: Mn2+, Mn4+, Co2+, Pt2+

Ethylbenzene NHPI

PINOAcetophenone

Data

Activator Ethylbenzene Ketone Alcohol

AcOH, NHPI Ctrl 79 9 0

No NHPI, PtC AcOH 78 0.1 0.1

Pt GraphC AcOH 56 26 7

PtBiC AcOH 50 24 8

PtC Supp AcOH 74 9 2

Synthesized PtC AcOH 55 26 10

• O2 known to oxidize Pt well

Data

Activator Ethylbenzene Ketone Alcohol

AcOH, NHPI Ctrl 79 9 0

No NHPI, PtC AcOH 78 0.1 0.1

Pt GraphC AcOH 56 26 7

PtBiC AcOH 50 24 8

PtC Supp AcOH 74 9 2

Synthesized PtC AcOH 55 26 10

• O2 known to oxidize Pt well

Data

Activator Ethylbenzene Ketone Alcohol

NHPI Cntl (No Mn) 74 20 3

MnO 25 53 6

MnO2 29 46 4

Mn2O3 36 45 5

Mn3O4 28 53 5

Mn(OAc)2 25 53 5

• All Mn activators performed similarly

• MnxOx surrogate to Mn(OAc)2

Jiang,J; Jing,Y; Zhang,Y; Jiao,J; Oxidation of Toluene, 2010

Data

Activator Ethylbenzene Ketone Alcohol

NHPI Cntl (No Mn) 74 20 3

MnO 25 53 6

MnO2 29 46 4

Mn2O3 36 45 5

Mn3O4 28 53 5

Mn(OAc)2 25 53 5

• All Mn activators performed similarly

• MnxOx surrogate to Mn(OAc)2

Jiang,J; Jing,Y; Zhang,Y; Jiao,J; Oxidation of Toluene, 2010

Data

Activator Ethylbenzene Ketone Alcohol

Control (NHPI) 83 14 3

Control (Co) 88 12 1

Co(OAc)2 19 73 2

Co(OAc)2 w/ MCBA 6 100 1

Co3O4 nanoparticles (commercial) 76 18 2

Co3O4 nanoparticles (synthesized) 51 41 6

Beller Co/CN catalyst 51 41 6

• Co(OAc)2 w/ MCBA has best yield

• Co3O4 nanoparticles vs. Beller catalyst

Ishii,Y; Catalytic Oxidation,J. Org. Chem, 1997 62, 6810-6813

Data

Activator Ethylbenzene Ketone Alcohol

Control (NHPI) 83 14 3

Control (Co) 88 12 1

Co(OAc)2 19 73 2

Co(OAc)2 w/ MCBA 6 100 1

Co3O4 nanoparticles (commercial) 76 18 2

Co3O4 nanoparticles (synthesized) 51 41 6

Beller Co/CN catalyst 51 41 6

• Co(OAc)2 w/ MCBA has best yield

• Co3O4 nanoparticles vs. Beller catalyst

Ishii,Y; Catalytic Oxidation,J. Org. Chem, 1997 62, 6810-6813

Data

Activator Ethylbenzene Ketone Alcohol

Control (NHPI) 83 14 3

Control (Co) 88 12 1

Co(OAc)2 19 73 2

Co(OAc)2 w/ MCBA 6 100 1

Co3O4 nanoparticles (commercial) 76 18 2

Co3O4 nanoparticles (synthesized) 51 41 6

Beller Co/CN catalyst 51 41 6

• Co(OAc)2 w/ MCBA has best yield

• Co3O4 nanoparticles vs. Beller catalyst

Ishii,Y; Catalytic Oxidation,J. Org. Chem, 1997 62, 6810-6813

ConclusionSome success with new activators

Mn activatorsLiterary work still performs bestThanks to Damian, the Stahl Lab, Professor Cui

References Fox,T.;Kollman,P. C-H Bond Dissociation Energies in Toluene,

1996 100, 2950-2956

Ishii,Y; Catalytic Oxidation,J. Org. Chem, 1997 62, 6810-6813

Einhorn,C; Einhorn,J; Marcadal,C; Oxidation of Organic Substraits, Chem Community, 1996

Sung,S.K.; Rajagopal, G; Efficient Aerobic Oxidation, Inha University, 2006, 402-751

Jiang,J; Jing,Y; Zhang,Y; Jiao,J; Oxidation of Toluene, 2010

Lao,Yu-Ran; Handbook of Bond Dissociation Energies, 2003, 3.1,3.4