A facile route to Cr(CO)5(CX) (X  S, Se) complexes

Cl Cfremistry,132 (1977) Cl-

dOUlRtl~of~~nometai~ic .@ Wsmier

~uoiaS.A.,Lausanne-_nt~in'KeNetheriands

Preliminary

A FACILE

Ann M. Paul

Cczrznxmication

ROUTE

TO

English,

LeMfaux?

Cr(C0)5(CX)

Keith

and

R. Plowman,

28 February.

Ian

COMPLEXES

S. Butler*,

GLrard

Jao~en"~,

Thdpot t

Jean-Yves

Department of Chemistry, H3A 2K6 and TLaboratoire de Rennes, 35031 Rennes

Received

(X = S, Se)

McGill University, Montreal, Quebec, Canada de chimie des organomEtalliques, Universits Cedex, France

1977

Summary Reaction gives

of

Cr(CO)5(CSe),

containing

only

the

CO and

(g6-C6H5R)Cr(CO)2(CS) much

all

higher

yield

While

numerous

the Group

still

first CSe

than

the

VIIB

rare

and

and

(X = S,

Se)

are

(N = Cr, MO, complexes

W)

CO afford

by

have

[1,2],

restricted

been

substitution

by various

monodentate

of

reported

metal

in

report

of

the

iigands

almost

Re)

synthesis

1.

The

ligands

in

(L) to fern

(3.11 of

reactions

arc

Arene

(1)

(n6-Arrnc)M(C0)3 fac-M(CO)3L3

[6,7].

Reaction

1 may

be

carried

out

under

either

low

or high

are

type,

the

Cr(CO),(CX) + of arene

for

selenocarbonyls

(M = Mn,

in reaction

3C0 ___3

to the

complex

Cr(CO),(CS)

to complexes

We now

the method

+

pressure

method.

complexes

151.

CO under

reactions

(T15-&,X,)M(CO),(CSe)

(n6-Arene)Cr(CO)2(CX)

analogous

with

VIII.metals

and ~~~-RuC~~(CO)(CS~)(PP~~)~

directly

Similar

literature

thiocarbonyl

excess

of a selenocarbonyl

ligands.

(~6-C6H,C0,CH3)Cr(C0)2(CSe),

Cr(CO)5
example

(R = H, C02CH3)

VIB,

extremely

with

(n6-C6B6)Cr(CO)2(CSe)

pressure

C2 l

conditions. so?ution placed bp

In a typical (So ml)

of

in a Carius

repeated

into

tube

is sealed

off

the

pressure

experiment,

(n6-C6H6)Cr(CO)2(CSe) -7G

(capacity

freeze-thaw

introduced

low

(0.3 ~1)

cycles-

Carbon

from

a calibrated

tube

g.

and

I mmol)

the

[3,8]

solution

monoxide

is

is degassed

(8 mmol)

vacuum

placed in a SO0 oil bath.

and

a tetrahydrofuran

Fs then

manifold

and

the

tube

Under these conditions, the

ol~vimum pressure in the tube assuming that 110 CO gas is dissolved is 8 azz azxd fornation

If CI-(C!O)~(C!S~) is cc~1p1et.e in 3.5

c.arbonyl

reactions

example,

when

ti acetone

have

250

atm

pressure,

u?.

the

solvents of

accomplished

is reacted the

the

the

and

Ci(C0)3(CX)

Cr(CO)5(CX)

(25O/l

x 10e4

t,emperature

line

nitrogen

complexes torr)

traps

based

on

latter

range

is appreciably

malgam

by the

not

from

It should

be obtained residues

large

in

three

cold

fraps: nitrogen

pure

the

3-61

C12CS.

yields

snples

typically

yield

obta%ned

and

here

for of

regenerated

Cr(C0)

the

sodium

of

unlike

5

The

for

involves

treatment

Moreover,

separation

are

on Cr(C0)6.

[lo] which

of

two higher

based

the

the (CS)

does

thiocarbonyl

in the

reactions.

that the literature approach would be

2nIlpossiblefor the synthesis of Cr(CO)S(CSe) oving of C12CSe.

is best

in the

method

05 Cr(C0)6

this

remaining

described

chemical

that

sublimation

tetrahydrofuran

nethod

aaourzts

be nentioned

than

vork

to the high

by vacuum

The

under

product

oting

Analytically

2nd 30-50X

-with excess

or

of

and

chloroform/liquid

finger.

literature

the DRY

physical

the

also

(-78“).

higher

current

anions

roufe,

neccessitate

product

can

of Cr(CO)6

caibonyl

t2iophosgene

(-4Sc).

(n6-Arene)Cr(CO)2(CX)

reduction

resulting

slush

an ice-cooled

73-952

Cr(CO>5(CS)

a sequence

thio-

For

701

Durtig

found

the

191 dissolved

at

carefully

using

ice

g, 3.5 -01)

in 3 h.

We

Only

pressure.

CO in an autoclave

extremely

of th e Solid

onto

(1.0

complexes.

acetone/dry

at high

is complete

be ramoved

on a vacuum

(-63")

vith

reaction

must

cilorobenzene/liquid slush

studled

(r16,6~5c02~3)cr(C)~(CS)

(70 ml)

volatility

so far been

h.

to the non-existanse

c3

The new selenocarbony‘l to~plex, CZ(CO)~(CS~). is a highly volatile, deep-yellov, crystalline solid that sublimes before melting asd has a characteristic odour reminiscent of CSe2.

It

is

air-stable .and soluble

without decomposition in all common organic solvents.

icits

msss

The parent ion

spectrum is consistent with the abundances of the naturally

cccurring isotopes of chromium -2co

is Cr(CO),(CSe)*

and selenium.

> Cr(C0)3(CSe)+,

stepvise loss of CO to give Cr(CSe)+, loss until Cr(CSe) Cr-CSe bonding.

+.

+

degrades to Cr

The non-appearence

line -with the knovn instability of

The initial fragmentation

following which there is

That there is no evidence for CSe

is tentatively indicative of strong of a peak attributable to CSe+ is in CSe

itself 1111.

The vibrational

spectra of the complex are closely similar to those of Cr(CO)3(CS)

1121

and are in accord with the expected Cbv molecular symnnetry. In its IR spectrum in s-hexane,

the complex exhibits three V(C0) modes at 2093m

(=y>,

203lm (ST)

and 2OOOvs (e-1cm-1 and one u(CSe) mode at 1077s ($1

cm-l.

The V(C0) region in the Kaman spectrum (Kr* excitation, 548.2 IUD)

of the solid is complicated by extensive solid-state-splittings

indicative

of more than one molecule per unit cell; the v(CSe) mode appears as broad, media-intense

peak at 1093 cm

In principle., reaction

11

2

.

1 could be extended

to the synthesis of the

other Group VIB H(COj5(CX) complexes provided that suitable examples of the presently unknovn (n6-Arene)H(CO)2(CX) precursors could be.prepared. There has been con&ierable thiocarbonyls

with

the

interest lately in the chemistry of metal

HfCO>5
complexes receiving particular attention

because of their high symmetry and close structural similarity to the matal hexacarbonyls

[e.g., 10.12-141.

We anticipate that Cr(CO)5(CSe) will

be subject to similar attention in the future, especially since diatomic

CSe has never been isolated Ill], and the discovery of this relatively simple selenocarbonyl

complex affords the best opportunity to date for

comparing the bonding properties of CSe With those of the isoelectronic ligands, CO and CS.

Acknowledgements This research was supported by generous grants from the following sources: National Research Council of Canada, Quebec Departnent of Education and C.N.R.S. (France). References 1.

1-S.

2_

I-S_ Butler, Accts_ Chem. Res., submitted for publication.

3.

I.S. Butler, D. Cozak and S.R. Stobart, 3. Chem. Sot., Chem. Commun., 103 (1975).

4.

I.S. Butler, D. Cozak and S.R. Stobart, Inorg. Chem., in press.

5.

G.R. Clark, K.R. Grundy, R-0. Harris, S.M. James and W.R. Roper, J. Organometaf. Chem., 90, C37 (1975).

6_

G-R. Dobson. I.W. Stola and R.K. Sheline. Adv. Inorg. Chen. Radiochen-. 8, 1 (1966).

7.

A. Pidcock, J-D. Smith and B.W. Taylor, 3. Chem. Sot. (A), 1604 (2966) and references cited therein.

8.

D. Cozak, Ph.D. Thesis, McGill University, Montreal, Quebec, Canada, 1977.

9.

G. Jaouen, Tetrahedron Lett., 52, 5159 (1973); G. Jaouen and G. Sinonneaux. Inorp. Synth.. XIX, in press.

Butler and A.E. Fenster, J. Organonetal.

Chem.,

66, 161 (1974).

10. E-D. Dombek and R.J. Angelici, Inorg. Chen., 15, 1089 (1976) and references cited therein. 11. R. Steudel, Angew. Chen. Internat. Ed., 6, 635 (1967). 12.

1-S.

Butler , A. Garcia-Rodriguez, Inorg. (hem., 15, 2602 (1976).

R.R. Plowman and C.P. Shaw III,

13. M. Poliakoff, lnor . Chem., 15, 2022 (1976). 16. D.L. Lichtenberger and R.F. Fenske, Inorg. Chem., 15, 2015 (1976).