The oligoalumosiloxanes {[Ph
2
SiO]
8
[Al(O)OH]
4
∙2,5Et
2
O∙HO
t
Bu} (
6
) and {[Ph
2
SiO]
8
[Al(O)OH]
4
∙2Et
2
O∙2HO
i
Pr} (
7
) have been obtained from the reaction of diphenylsilanediol with aluminium-
tri-tert
-butoxide and aluminium-
tri-iso
-propoxide in ethyl ether with reasonable yields. In a 1:1 molar mixture of toluene and the respective alcohol (
iso
-propanol or
tert
-butanol), the ethyl ether molecules in {[Ph
2
SiO]
8
[Al(O)OH]
4
∙4Et
2
O}, in
6
or
7
can be completely displaced forming the compounds [Ph
2
SiO]
8
[Al(O)OH]
4
∙
4HO
i
Pr (
8
) and [Ph
2
SiO]
8
[Al(O)OH]
4
∙
n
HO
t
Bu (
9
). Whereas
6
,
7
and
8
are crystalline,
9
is obtained as a viscous liquid. An X-ray structure determination on {[Ph
2
SiO]
8
[Al(O)OH]
4
∙3Et
2
O∙HO
t
Bu} reveals different bonding modes of the diethyl ether molecules to the oligoalumosiloxane compared to the tert-butanol, which forms two hydrogen bonds (one to the OH-group of the inner Al
4
(OH)
4
cycle and one through the alcohol OH-group to a Si-O-Al moiety The alcohol adducts have been characterized in solution through
1
H-,
13
C- and
29
Si-NMR and show dynamic equilibria between the oligoalumosiloxane [Ph
2
SiO]
8
[Al(O)OH]
4
and the alcohol molecules.