The complexes [NbI2(CNtBu)6]I
(1), [NbI2(CNtBu)4(tBuNHC⋮CNHtBu)]I (2), and
cis-[NbI(CO)2(CNR)2dppe] (R = tBu (3a), Cy
(3b)), have been prepared
by oxidation of [Nb(CO)6]- with iodine
in the presence
of isonitrile either in a direct reaction (1 and
2) or, in
the case of 3, by substitution in the intermediate
[NbI(CO)4dppe]. While 1 and 3 are
generated in absolute
THF, 2 forms in moist THF. The X-ray
structure
analysis of 1·THF, 2, and
3b·toluene reveals trigonal-prismatic basic structures with the iodines capping
tetragonal faces. 1 and 3b exhibit
interatomic C···C
distances sufficiently close to enable C−C coupling.
The
relevance of the coupling product 2 for reductive
C−C
coupling mediated by low-valent niobium is discussed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.