The selective amination of carbonyl compounds using iron pentacarbonyl

Tetrahedron Lettera No. 22, PP 1879 - 1880, 1974.

PergamonPress. Printed in Great Britain.

USING IRON PENTACARBONYL THE SELECTIVE AMINATION OF CARBONYLCOMPOUNDS

Yoshihisa

Masato Department

Masakazu

Watanabe,

of

Tanaka,

Hydrocarbon

Yamashita,

Take-aki

and Yoshinobu

Chemistry,

Kyoto

Mitsudo,

Takegami University,

Kyoto,

Japan

(Received in Japan 15 April 1974; received in UK for publication22 April 1974)

There aldehydes

are

or ketones

reaction

are

and yields

or ketones converted

advantages

of

this

simple,

the

boiling

carbonyl

but

are

using

iron

over

proceeds

compounds,

the

many of

to

reductive

them normally

report

amines

the

the

facile

and the

require

of drastic

ones

under

yields

the

variety

reaction. are

mild

of

and selective

A wide

by this

previous

smoothly

amination

low. 1,2)

pentacarbonyl.

secondary

method

for

often

we wish

into

reaction

available

amines,

communication,

aldehydes

groups

methods

with

conditions

In this of

numerous

that

amination

carbonyl

The principal the

operation

conditions,

is

applicable

corresponding

to

amines

low

are

exellent. In the or a ketone hydroxide generate S-10

general

and 11 mm01 of solution

the

and 1.5

an alcoholic

an amine were ml (11 mmol)

hydridotetracarbonylferrate

hr at room temperature

absorbed

to

procedure,

slowly

during

the

solution

added of

iron

one atmosphere

reaction.

Yields

isolation

or by glpc

analyses

reductive

aminations

are

listed

using

a 33 ml of

internal

in Table

1.

of

11 mm01 of

the

carbon products

standards.

potassium

[conditions

The mixture of

an aldehyde

1N alcoholic

pentacarbonyl

anion].‘)

under

of

which

was stirred

for

monoxide

which

were

determined

Some representative

was by

Woo.22

1880

Table

Reductive

aminations

Compound

No.

EXQ.

1.

of

carbonyl

Amine

Product

Benzaldehyde

Aniline

N-Benzylaniline

2

n-Butyraldehyde

Aniline

N-n-Butylaniline

100

3

Formaldehyde

Aniline

N-Methylaniline

91

4

n-Butyraldehyde

n-Butylamine

Di-n-butylamine

89

5

Acetone

Isopropylamine

Diisopropylamine

93

6

Cyclohexanone

Cyclohexylamine

Dicyclohexylamine

7”

Benzaldehyde

Aniline

n-Butyraldehyde n-Butylamine .__- .._.-. ^- ___.. __.. _ .-... . ___... *The reaction was conducted under argon

The reaction products

were

also

lower ferrate

carbon

mcnoxide,

at maximum with In the

of

of

proceeded

(Exp.

When the

a type

Yield

1

a*

under

compounds

2.6

Schiff

bases

condition

Other

with

to

of

amination are

give

applications

excess

carbon of

the

3.0

of

N-Benzylaniline

79 60

atmosphere

mixture

but

the

yields

this

of

of

benzaldehyde’and

N-benzylaniline

was obtained

compounds

regarded

ferrate

also

are

amines,

compounds

as intermediates.

The reduction

smoothly

under

mol/mol-KHFe(C0)4 reaction

with

of

proceeded

2) R. F. 3)

Borch

P. Krumholz

Organic

Reactions,

and H. D. Durst, and H. M. A.

J.

Q, 174 Amer.

Stettiner,

currently

explored

in our

(1948).

Chem. Sot.,

ibid.,

7l,

the

N-benzylaniline.

References W. S. Emerson,

the

aniline

tory.

1)

of

monoxide.

carbonyl

generally

with

100

Di-n-butylamine

atmosphere,

mol/mol-KHFe(C0)4

an absorption

reductive

argon

98

7 and 8).

reacted

N-benzylideneaniline

similar

No.

under

(%I

9l,

3035

3996 (1949).

(1969).

labora-

of