2 Homometallic Alkoxides

product metal aryloxide 1e,1f (Eqs 6.32 110 and 6.33 111 ).
Metal Aryloxides 459
FeCl3 C 4LiOAr P⊲Ph⊳C4 Br
! P⊲Ph⊳
LiBr
C 4 [Fe⊲OAr⊳4] C 3LiCl ⊲6.31⊳
Cl
where OAr = O Cl.
where ArO =
O
Cl
SnCl2
Ph
Ph
+ 3LiOAr Li
Ar
O
Ar
O
O
Sn + 2LiCl
(6.32)
.
2CrCl2⊲THF⊳2 C 10LiOPh THF
! [Li6Cr2⊲OPh⊳10⊲THF⊳6] C 4LiCl ⊲6.33⊳
The alkali metal is typically bound to the aryloxide oxygen atoms, although in a
number of cases it has been shown that interactions between sodium and the phenoxy
ring of aryloxide ligand are an important aspect of the bonding in the mixed metal
cluster (Eq. 6.34 112 ).
where ArO =
O
Pr i
Pr i
Ar
NdCl3 C 4KOAr ! [KNd⊲OAr⊳4]n C 3KCl ⊲6.34⊳
.
Another method for the replacement of chloride by aryloxide at transition metal
centres is utilizing aryl-ethers. In this case the formation of the metal aryloxide is
accompanied by the elimination of either alkyl or trialkylsilyl chloride (Eq. 6.35 113 ).
where ArO =
NbCl5 C Me3SiOAr THF
! Nb⊲OAr⊳Cl4⊲THF⊳ C Me3SiCl ⊲6.35⊳
O
Me
Me
.