Adducts of uranyl carboxylates

INORG.

NUCL..

CHEM.

LETTERS

Vol.

5,

pp.

ADDUCTS

101-104,

1969.

Pergamon

Press.

Printed

In

Great

Britain

OF U R A N Y L C A R B O X Y L A T E S

T. H. Siddall,

III and W. E. S t e w a r t

S a v a n n a h River L a b o r a t b r y E. I. du Pont de Nemours and Co. Aiken, S o u t h C a r o l i n a 29801 and R. L. M c D o n a l d U n i v e r s i t y of H a w a i i ~Recelved 17 Oc~ber 1968)

In an e a r l i e r resonance

(PMR)

report, (I) we d i s c u s s e d

spectra

of a c o m p o u n d

UO2(CH3CO2)2"2[(i-C3H?O)2P(O)CeHs]. :from PMR s p e c t r a formulation

and chemical

is in error;

•(i-C3H?O)2P(O)CeH5

of five for the u r a n y l thesize their

a variety

group

prepared

a larger variety

identified

them by PMR,

we have not o b t a i n e d type U O 2 ( R C O 2 ) 2 " L (C2H5)2CH,

IR,

(A), these

include

and s e v e r a l

substituted

empirical

formulae

Analytical We have

types

and

spectroscopy,

For compounds

but

of the

R = i - C s H 7, CeHsCH 2, and

these

and o r g a n o p h o s p h o r u s

include

h = bipyridyl

o-phenanthrolines.

and o r g a n o p h o s p h o r u s

formulation

of the same

of amides

(B),

and examine

in the table.

analyses.

number

led us to syn-

carboxylates

and n e a r - v i s i b l e

variety

For U O 2 ( R C O 2 ) 2 " h

empirical

of a c o o r d i n a t i o n

are given

of adducts

compounds.

Amides

is UO2(CH3C02) 2

spectra near 4000 ~.

elemental

and L=a wide

formula

of uranyl

adducts

to be

that this e m p i r i c a l

in this c o m p o u n d

of adducts

typical

analysis

Observation

PMR and n e a r - v i s i b l e

data for some

that we reported

We have now d e t e r m i n e d

the correct

(I).

the proton m a g n e t i c

(A).

ligands

Panattomi

gave adducts

et al. (2) report

UO2(CHaCO2)2"(C6Hs)~P(O)

101

of the the

and UO2(CH3C02) 2"

102

URANYL CARBOXYLATES

Vol. 5, No. 2

TABLE Analytical Data

Empirical Formula

C({)

H(%) N({)

P(~)

U(~)

U02(CHsC02) 2-

Found 30.03

[(C2Hs)~CHCH2]2P(0)H

Calc. 31.69

5.25 5.~9

0 0

4.94 5.Ii

Not determined

U02(CHsC02) 2. (2- C4Hs) sP(O)

Found 31.13 Calc. 31.69

5.49 5.49

0.04 0

5.29 5.1

37.7 39.3

U02(CH3C02)2" CH3C(0)N(i-CsH7)2

Found 27.31 Calc. 27.13

4.38 4.36

2.39 2.64

0 0

Not determined

U02[(CHs)sCC02]2"

Found 28.72

4.48

2.58

0

41.7

HC(O)N(CH~) 2

Calc. 28.63

4.62

2.57

0

43.7

U02](CHs)sCC02] 2" ( i- CsHTO)2 P(0) C6Hs

Found 36.64 Calc. 36.98

5.15 5.22

0.13 0

4.46 4.43

33.3 32.4

U02[(CHs)sCC02] 2" [ (C2H~)2CHCH2 ]2P(O)H

Found 37.99 Calc. 38.26

6.70 6.57

0 0

4.61 4.49

35.0 32.8

U02[(CH3)sCC02] 2" o- phenanthroline

Found 30.34 Calc. 40.50

4.07 4.02

4.26 4.20

0 0

36.5 37.8

(CeHs)sAs(0)

for similar compounds.

X-ray data (21 showed that

these compounds are dimers in the solid state.

The molecular

weight of UO 2[(CH3)sCC02]2.(i-CeHT0)2P(O)C6H5

(II) in benzene is

I186; the monomeric molecular weight is 714.

For U02[(CHs)3CC02] 2

•CHsC(O)N(i-CsHT) 2, the molecular weight in benzene is 1209; for the monomer it would be 619.

The near-visible spectra of all

soluble compounds of type A were found to be essentially identical in chloroform solution or in paraffin oil mulls.

The near-visible

spectra of uranyl compounds are very sensitive (s-5) to changes in coordination to the uranyl group.

Vol.-5, No.

URANYL CARBOXYLATES

2

A dimeric for

structure

the a c e t a t e

CH3

temperature. (~)

also

signal

103

explains

the s t r o n g

PMR d o u b l e t

of C o m p o u n d

I in CDCIz

at low

A structure

such

as

CH3

0

I

0

L~ I /O--C--O.... I/L ,-,.-- U. ~U.-.o /~I I "O--C--O I\n \ I

0

/ c/v

CH-5 would rate

allow

two d i f f e r e n t

PMR signal.

belong

to one

higher

polymers

have now the

CH3

or m o r e

protons

the PMR signals

kinds

However,

the

a similar

of the

poorly

in a q u a n t i t a t i v e

manner.

that

! and

large,

tion.)

Similar

:>ther c o m p o u n d s

as

multiplicity of type

spectral

not

soluble

behavior

ppm d o w n f i e l d ~equal At-64°?,

these

intensity

= 1.0;

~C.5. fiftb

1.36

coordination

,,is~!e

spectra

similar

to those

The

(B),

ppm,

of the

We from

as w i t h

,Jifficult

I,

to w o r k

is an i n d i c a t i o n species

in solu-

in the P~IR s p e c t r a

at

~0.5;

a singiet

of

].~9

opm,

1.41, acts

solutions

adducts

entirely

ppm,

].84,

as a ligand

aroun::l the u r a n y l

pivalate

a doublet

smaller

1.29

~0.5;

(the

complex

is o b z a i n e d

becomes

signals:

chlorofomr

amine

but even more

in CDsCOCD3

this

broad

probably

of acetnne

are

-20°C,

signal

position

heterocyclic

I]Os(RCOs).i:)

:~issolved

five

<~DsCOCD s itself

and

polymeric

similar

At -33°C,

(larger

become

However,

of itself

observed

gives

Above

from TMS.

intensity

above.

A.

whe~

in CDCI~).

must

in the PMR signals

resolve:],

possibly

a sepa-

-- e i t h e r

structure

of !I.

(This

was

U O s [ ( C H s ) e U C 0 2 ! 2 i~self PMR

ion

species

of the

multiplicity

each w i t h

CHs signals

molecular

isomers

with

II exist

two s m a l l e r

pivalate

are broad,

CH 3

of CHz groups

additional

or c i s - t r a n s

observed

0 ""-C\

CH3

at

group.

1.4~ of

l.,q~, ppm)

relative

-0.2;

and

an~

occupies

of uranyl

different

from

1.93, the

The near-

of U O 2 [ ( C H z ) s C C O s ] 2 are

solutions

is

very

of U O s [ R C O s ] s ' L . carboxylates, adducts

of type

A.

104

URANYL CARBOXYLATE$

Voh 5, No. 2

The molecular weight

of UO2[(CHs)3CCO2]2-o-phenanthroline

is 578 in chloroform

(monomer weight

quency part of the near-visible greatly enhanced observed

in intensity

in the spectra.

six coordination

is observed

attached

of

to the

even at low temperature.

exist as hexacoordinate dimers

our investigations

The adducts

tions of the separate

monomers

in

(or high polymers)

in water,

(where required)

The pivalates

of their high solubility

of adducts

are easily assembled

components

and then precipitating

in particular

of uranyl

by mixing solu-

ethanol,

or CH2CI 2,

by adding a nonpolar

are most useful because

in such solvents

as chloroform.

UO2[(CHs)sCC02] 2 is easily prepared by exchange acetate with pivalic

It is

of type A.

We are continuing

solvent.

is characteristic

groups

to the pentacoordinate

found for compounds

carboxylates.

to the other progressions

This enhancement

that these compounds

contradistinction

relative

is

The PMR spectra are sharp and well resolved;

no extra multiplicity apparent

The lower fre-

spectra of type B compounds

with three chelating

uranyl group. {3-5)

is 653).

(III)

of uranyl

acid at reflux. Acknowledgment

The

information

contained

in this article

during the course of work under Contract U. S. Atomic

was developed

AT(07-2)-I

with

the

Energy Commission. References

I) T. H. SIDDALL, III and W. E. STEWART, Inorg. Nucl. Chem. Letters 3, 279 (1967). 2) C. PANATTONI, G. BANDOLI, R. GRAZIANI, and U. CROATTO, Chem. Comm., 278 (1968). 3) E. RABINOWITCH and R. L. BELFORD, Spectroscopy and Photochemistry of Uranium Compounds, The MacMillan Co., New York

( 1964 ). 4) L. L. BURGER, in Aqueous Reprocessing Chemistry of Irradiated Fuels, Eurochemic Symposium in Brussels (1963). 5) T. H. SIDDALL, III, R. L. McDONALD, and W. E. STEWART, J. Mol. Spectry. (in press).