Helvetica Chimica Acta ± Vol. 84 (2001)
907
Transacetalization Reaction. The catalyst precursor (2.5 mmol) was added to a CH
2
Cl
2
soln. containing the
aldehyde (or ketone) (5 mmol) and the acetal (5 mmol). After the reaction was complete (GC monitoring), the
soln. was filtered over neutral Al
Acetalization of Benzophenone. The catalyst precursor (RhFS
10 ml) soln. of benzophenone (1.82 g, 10 mmol), MeOH (1.60 g, 2.0 ml, 50 mmol), and MOF (2.12 g, 20 mmol).
The soln. was stirred for 5 days at r.t. (GC monitoring). Then, the soln. was filtered over neutral Al and
/MeOH: 1.95 g (80%) of 1,1'-(dimethoxy-
); 3.17 (s, 2 MeO).
2
3
O .
1
2 2
) (7.0 mg, 5 mmol) was added to a CH Cl
(
2
O
3
evaporated. The crude product was recrystallized from CH
2
Cl
2
1
methylene)bis[benzene]. H-NMR (250.13 MHz, CDCl
3
, r.t.): 7.41 (m, 2 C
6
H
5
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Received December 20, 2000