Meso-nitro- and amino-aetioporphyrins

Tetrahedron Letters No.24, PP. 1349-1332, Printed in Great Britain.

PIESO-NITRO-

AND

and

THE of

recent

Communication

the meso-nitro

that has

we have

examined

the

reported

by Fischer

di-,

and

trinitro

derivatives

were

not

defined.

for of

the

dinitro

of a carbon

separation observations copper with

mixed

2

which

nitrate

Satisfactory Communication aetioporphyrin

was

have

been

I gave

derivative removed

obtained

all

of the

obtained.

layer

a mixture

compounds

of two

has

also

reaction

cupric

nitrate

and

acetic

I could

been

acid

contaminated

mono-,

nitro

effective

at

12-13O

with

temperature mentioned

nitration

either

directly The by

the the

a bright

for 2 hr.

period, and

the

by

isomeric

thin

red

porphyrin

in this

derivatives

obtained

of

with

of the

a little

on alumina

for

I formed

groups

of

chromatography

anhydride.

be separated

1549

reaction

of the

nitric

a longer

dinitro

complex

This

described

In agreement

at room

Using

to record

of a solution

by nitration

anhydride

I.

rho

is particularly

copper

dinitroaetioporphyrins

2

us

by chromatography

Thin

corresponding with

25%

preparation

prompts

mononitroaetioporphyrin also

for

with

derivatives.

in acetic

analyses

on the

positions

nitration

acid

was

nitro

the

that

solutiom

of Fischer,

complex

cupric

found

solution.

petroleum of the

coworkers,

although

which

tetrachloride

Stephenson1

of aetioporphyrin

55% of a mononitro compound,

benzene-light

and

and his

I in 63% sulphuric gave

30 min.

1964)

of octaethylporphyrin

been

aetioporphyrin

Chemistry,

28 April

nitration

lie have

Oldfield

University.

by Bonnett

derivative

Diane

of Organic

Nottingham (Received

Pergamon Press Ltd.

AXINO-AETIOWEPHYEINS

A. U. Johnson Department

1864.

layer

Meeo-nitro- and amino-aetioporphyrins

1550

chromatography bensene

or in a steady

- 3096 sulphuric

state distribution

acid as the solvent

vigorous

conditions

obtained

and this was also converted

All of theSo

of nitration,

products

by interpretation

spectra,

which have been

and

are present Uhen that

compared

Table).

group

must

mononitro

The occupy

in the ring and

of acid

mesoaminoporphyrin

prepared. amine

was

derivative The

on

to be meso-substitution resonance

trifluoracetic

spectrum shows

when

(n.m.r.1

acid

(TFA)

the porphyrins

by

with

the

by movement

of these

imino

effects

of the

trinitro

signals

indicate

that

the

ring.

by loss

nitro

The

decrease

of planarity

properties

compared

field

of the

with with

of

the various

aetioporphyrin

as expected.

given

the

I with

corresponding

to be described.

The

spectrum

as its salt) the

derivative I have

of the aminoporphyrin showed

effect

of the

stannous

meso

a remarkable

of the and

also

and

protons

first

the

been

divergence amine

and

the

(in TFA,

protonated

imino

chloride

aminoporphyrin,

copper

of monoaminoaetioporphyrin

of absorption

to higher

to lower

associated

derivative

qononitroaetioporphyrin

I and

groups

groups

partly

in the

of the signals

on the macrocyclic caused

I itself,

decrease

a substantial

tha electron-withdrawing

greater

has

of aetioporphyrin

of the meao- and $-alkyl

is presumably

n.m.r.

present

of aetioporphyrin positions

derivative.

magnetic

solutions,

indicated

associated

in the

even

Reduction

N-acetyl

derivative

Displacements

are

hydrochloric

(DTFA)

a me.so position

partly

of proton

I itself

mainly

the n.m.r.

magnitude

current

Substituent. types

rith

of those

(see

ring

acid

with the protons

and

field,

the

measured

of the ring durrent,

associated

have been shown

I could be

as the dications.

of the

strength

to its copper

using

Under still more

system.

of their nuclear

deuterotrifluoracetic

apparatus

trinitroaetioporphyrin

compounds

nitro

No.24

when

the

from

that

group

exceeds

on the

that

of

3

Ueso-nitro-

No.24

three the

nitro

side

amino

groups.

chain

compound

The

methyl than

and amino-aetioporphyrins

spread

groups

that

of absorption

is appreciably

observed

(0.4G7)

qononitroaetioporphyrin

I.

This

but

the

aminium

it is relevant

would

cause

less

that

distortion

of

effect

may

group,

1551

(0.197) less

in the

in the be

case

spectrum

due

being

associated

of the

of

to several

smaller

with

than

causes, nitro,

the molecule.

TADLE N.m.r.

Signals

of Aetioporphyrins

except

where

Meso Groups(s)

Compound

otherwise

-1mino Groups(s)

I (TFA

solution

stated)

B-Uethyl Groups(s)

S-Ethyl Groups

w (cl) Aetioporphyrin

I3

Uononitroaetioporphyrin I

m,(t)

-1.0

14.8

6.2

5.7

8.16

-0.77(2iB6) -0.68(l;y)

13.72 14.17

6.36

5.89

8.29

6.22 6.31 6.54

5.69

8.2

6.63 6.79 6.93

6.55

8.53

6.53 6.78 6.89

6.42

8.47

6.37

8.33

5.9

8.26

2:: (in DTFA)

-1.11(l) -1.19(2)

-0.54

Trinitroaetioporphyrin I

-0.76

(in DTFA)

Uonoaminoaetioporphyrin I

Honoacetylaminoaetioporphyrin

9 = singlet.3

11.7

I

+0.56(2;Si) +0.99(li y,

9.01 10.49

-0.68(2ied) -0.59(1; Y)

13.3 13.48 14.3 14.4

q = quarteti

t = triplet

k$Z 6:92

:::5 6.69

1552

Yeso-nitro- and amino-aetioporphyrins

I4.m.r. spectra in deuteratad

trifluoracctic

the nitro compounds to those

in TFA.

observed

of solutions

of the meso sub8tituted

the entire spectra

No exchange

rare shifted

of meso protons

protons

at room temperature

was heated

for deuterium.

of deuterium

exchange

substitution

no doubt being facilitated

of

of

in the porphyrin

the unprotonated

bands associated

However

exchanged

When the amino

series,

the electrophilic

by the presence

amino compound.

It is of interest

group on the spectrum

meso

This is the first example

of a small

In this case the positions

with the alkyl substituants

TPA and DTIA solution. acetylarino

was

e.g.4

y-proton

after about 20 min.

relative

in DTFA at 100° for one hour, the remaining

were also exchanged

quantity

with deuterium

I, the meso

and with

downfield

of other porphyrins.

in the case of monoaminoaetioporphprin

compound

aetioporphyrins

acid (DTFA) were also determined

in common with the behariour

with deuterium

No.24

were identical

in both

that the effect of the

of aetioporphyrin

I approximates

to

that of one nitro group. Further

studies

of

these compounds

are in progress.

REFERENCES (1)

R. Bonn&t

and G. P. Stephenson,

(2)

H. Fischer

and

H. Fischer

and U. Neumann,

(3)

R. J. Abraham, 3468

(4)

A.

A.

Triebs,

H.

Proc. Chem. Sot., 79 (1964).

Annalen, Annalen,

Jackson,

466, iWl

188

(1928)s

222, 225 (1932).

and G. Y. Kennar,

J. Chem. Sot.,

(1961).

R. B. Woodward

and V. gkarii, J. Amer. Chem. Sot., $2, 4676

(1961).