Complexes of difluoroethyne

P78

328

COXPLEXES

Heike

OF

DIFLUOROETHYNE

Michael-Schulz,

Dagmar

Preugschat

and Dieter

Lentz

Institut fiir Anorganische und Analytische Chemie der Freien Universitgt Berlin, Fabeckstr. 34-36, D-1000 Berlin 33, FRG

Difluoroethyne

is a very

unambigiously Nevertheless molecule

on transition

a coordinated

coordinated

difluoroethyne

lost its idendity be seen

Thus,

the first

ligand.

However,

forming

of a

difluoroethyne

carbon close

According

atoms

might

as can

bent C-C-

better

be

cluster. complex

is obtained

by

with

to the crystal ligand

has

centers

of 145 ppm and a strongly

dichloride

fragments

readily

example

to four metal

way a difluoroethyne

the difluorethyne

tetracarbonylcobalt

occurs

of the compound

contains

of the CoFesCz

tetracarbonylcobaltate.

formation

ligand.

length

of difluorofumaric

determination

with

the difluoroethyne

as a part

In an alternative reaction

of Fez (CO)9 (~~-CF)Z

due to coordination

from a C-C bond

F moiety. regarded

this

determination

that the cluster

has been

and stabilize

carbon-carbon

difluoroethyne structure

which [ll.

centers.

reaction

and Cp*Rh(CO)z,

The crystal revealed

to generate

metal

expansion

molecule,

only recently

it is possible

In the cluster C~*CO(CO)Z

unstable

characterized

bridges

structure

two

in the very unusual

pa-vl-ql

coordination.

1 H. Biirger and S. Sommer,

J. Chem.

Sot.,

Chem.

Comm.,

in press.