Type of compound:

Aldehyde

Alcohol

Amine

Ketone

Identify an Unknown

1. Physical PropertiesMelting point or boiling point

2. Functional Group

Infrared spectrum

NMR Spectrum

Solubility

Classification Tests

3. Solid Derivative

Procedure

Distill your unknown and note the boiling point

If can’t distill or not enough sample use this technique.

Measure boiling point of liquids

Carbonyl Group (1650 - 1725 cm-1)?

Yes No

Aldehyde Ketone

NMR

Aldehyde Ketone

+ -

Alcohol Amine

Broad OH in IR

Yes NoAlcohol Amine

(Basic?)3700 - 4000 cm-1

Yes

Primary or Secondary

No

Tertiary

Functional Group

NH2NH

NO2

NO2

Aldehyde or ketone

2,4-dinitrophenylhydrazine test

+ NH2NH

NO2

NO2

2,4-dinitrophenylhydrazone

C

O

NH2R C

OH

NHR

NRC

DNP Mechanism

Reagent: NaOH and I2 (NaOI)

CCH3

O

RI2, NaOH

RCOOH + CHI3Yellow

Iodoform Test

CCH3

O

RI2, NaOH

RCOOH + CHI3Yellow

CHCH3

OH

RI2, NaOH

RCOOH + CHI3Yellow

Iodoform Test

Iodoform Test

(NH4)2Ce(NO3)6 + ROH

(NH4)2Ce(NO3)5OR

+ HNO3

Ceric Nitrate Test for Alcohols

1. Odor

2. If not soluble in water they may dissolve in dilute aqueous acid (HCl).

3. Water solutions of amines are basic to litmus.

Amines

SO2Cl

Benzenesulfonyl Chloride

Hinsberg Test for Amines

Primary: Soluble. PPT if add HCl

Secondary: Insoluble

Tertiary: Tends not to react

Hinsberg Test for Amines

Aldehydes and Ketones

1. 2,4-dinitrophenylhydrazone

2. Semicarbazone

NH2NHC

O

NH2

semicarbazide

+ RC

O

R NNHCNH2CR

R

O

semicarbazone

Derivatives

O2N

O2N

C Cl

O

O2N

O2N

C OR

OROH

3,5-dinitrobenzoyl chloride

3,5-dinitrobenzoate

Alcohol Derivative

Primary and Secondary Amines

C

O

Cl + RNH2 C

O

NHR

Benzoyl Chloride Benzamide

SO2Cl + RNH2 SO2NHR

Benzenesulfonyl Chloride Benzenesulfamide

Amine Derivatives

B.p. =198-200o

DNP = 231-235o

Sample Unknown

Table

Structure of Unknown

C

O

CH3

acetophenone

Sample Unknown

B.p. = 80 - 85o

3,5-dinitrobenzoate = 119 - 121o

CCH3 CH3

H

OH

isopropyl alcohol

B.p = 106o

3,5-dinitrobenzoate 85o

CH2OHCH

CH3

CH3

isobutyl alcohol

B.p. = 160o

3,5-dinitrobenzoate: 108-110o

OH

H

cyclohexanol

B.p. = 155-157o

2,4-DNP = 158 - 160o

O

cyclohexanone

B.p. = 180 -183o

Benzenesulfonamide 110 - 112o

Benzamide 160 - 163o

NH2

aniline