Organic Synthesis Test 2

Front 1

Reduction of Enones to secondary alcohols

Back 1

NaBH4, CuI, MeOH

Front 2

Reduction of ketones and aldehydes

Back 2

NaBH4

Front 3

Reduction of esters, acyl chlorides, ketones, aldehydes, tosylates, nitriles and amides

Back 3

LiAlH4

Front 4

Reduction of enones (only C=O)

Back 4

Luche reduction - NaBH4, CeCl3

Front 5

Reduction to aldehyde oxidation level

Back 5

DIBALH - diisobutyl aluminium hydride

Front 6

Oxidation of alcohols to ketones and carboxylic acids

Back 6

CrO3, H2SO4, H2O - Jones reagent

Front 7

Oxidation of primary alcohol to aldehyde

Back 7

Pyridinium dichromate - NO water (PDC)

Front 8

Carbonyl --> Immine

Back 8

R-NH2

Front 9

Immine --> Amine

Back 9

NaCNBH3

Front 10

Azide --> Amine

Back 10

H2, Pd/CaCO3

Front 11

Carbonyl --> Acetal

Back 11

Diol and acid

Front 12

Carbonyl --> Oxime

Back 12

NH2OH

Front 13

Carbonyl --> Dithiane

Back 13

Thiol / Acid

Front 14

Nitrile --> Amide

Back 14

NaOH / H2O

Front 15

Nitrile --> Carboxylic acid

Back 15

H+ / H2O

Front 16

Carboxylic acid --> Acyl chloride

Back 16

SOCl2

Front 17

Removal of acetal/dithiane protecting group

Back 17

H2O / H+ (acetal) Hg 2+ / H2O (thiane)

Front 18

Protection of alcohols

Back 18

TBDMSCl - tertbutyldimethylsilyl + Imidazole

Front 19

Deprotection of alcohols

Back 19

Bu4NF (strong Si-F bond encourages removal of TBDMS)

Front 20

Hard nucleophiles - 1,2-carbonyl addition

Back 20

R-Li, R-MgBr, LiAlH4, NaBH4 / CeCl3

Front 21

Soft nucleophiles - conjugate (1,4-addition)

Back 21

R2-CuLi, RMgBr/CuI, RNH2, RONa, NaCH(CO2Et)

Front 22

Why is conjugate attack useful?

Back 22

Enolate intermediate can be captured by an electrophile

Front 23

Baeyer Villiger Oxidation

Back 23

Insertion of oxygen between carbonyl and most substituted carbon. MCPBA - metachlorobenzoic acid

Front 24

Hydration of double bond - least substituted alcohol

Back 24

i) BH3, THF ii) H2O2, NaOH

Front 25

Hydration of double bond - most substituted alcohol

Back 25

i) Hg(OAc)2 ii) NaBH4

Front 26

Addition of HBr - least substituted bromoalkane

Back 26

HBr, H2O2 - radical mechanism

Front 27

Addition of HBr - most substituted bromoalkane

Back 27

HBr - ionic mechanism

Front 28

Opening of an epoxide

Back 28

Acidic conditions - Least sub. alcohol
Basic conditions - Most sub. alcohol

Front 29

Kinetic vs. Thermodynamic enolates

Back 29

Kinetic - Least sub. H removed
Thermo - Most sub H removed

Front 30

Diels - Alder

Back 30

Diene and alkene
Heat

Front 31

Wittig Reaction

Back 31

Ph3P=CH-R, Ketone or aldehyde

Front 32

Preparation of a phosphonium ylide

Back 32

Phosphonium salt and base e.g.
Ph3P+CH3 Br- and NaH

Front 33

Reactive ylides

Back 33

R=alkyl, strong base needed, Z-alkenes

Front 34

Moderate ylids

Back 34

R= Ph or vinyl, moderate base, E/Z

Front 35

Stabilised ylids

Back 35

R= electron withdrawing, weak base, E alkenes, (WON'T REACT WITH KETONES).

Front 36

Back 36

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Front 39

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Front 40

Back 40

Front 41

Reduction of alkyne (Z)

Back 41

H2, Lindlar's catalyst (Pd/CaCO3)

Front 42

Reduction of alkyne (E)

Back 42

i) Na/NH3, ii) H2O

Front 43

Baeyer-Villiger oxidation mechanism

Back 43