Page 66 - Catalysts for Fine Chemical Synthesis Vol 1 - Robert & Poignant

50 hydrolysis, oxidation and reduction

spectrometer. High Resolution Mass Spectra were recorded on a Kratos profile
HV3, CIPOS, Fisons VG7070E spectrometer.
Some of the procedures described in the following chapters had to be carried
out under an inert atmosphere, nitrogen or argon, to minimize contact with
oxygen and moisture. It is then necessary to use Schlenk techniques including
the utilization of a vacuum line connected to a high vacuum pump and an inert
gas inlet. The use of such equipment requires experience in working under
anhydrous conditions.
All the procedures described were performed using dry solvents which were
freshly distilled under nitrogen. Tetrahydrofuran and ether were distilled from
sodium benzophenone ketal under nitrogen, and dichloromethane from cal-
cium hydride under nitrogen. Petroleum ether (b.p. 40±60 8C) was distilled.
Starting materials and solvents were used as obtained from commercial sup-
pliers without further purification unless specified otherwise.
Molecular sieves or magnesium sulfate were activated by heating at 500 8C
for 2±14 hours and cooled in a desiccator under vacuum.
Flash column chromatography was performed using Merck 60-silica gel (40±
63 mm) and solvents were obtained commercially and used as received.
Most of the reactions described in the following chapters were monitored by
Thin Layer Chromatography (TLC) using plastic TLC plates coated with a thin
layer of Merck 60 F 254 silica gel. The products were detected by using an
ultraviolet lamp or the TLC plates were treated with p-anisaldehyde reagent,
prepared as explained below, and then heated to 120 8C to stain the spots. After
visualization and measurement, the R f values were recorded.

PREPARATION OF p-ANISALDEHYDE REAGENT

Materials and equipment
. Ethanol (370 mL)
. Concentrated sulfuric acid (14 mL)
. Glacial acetic acid (4 mL)
. p-Anisaldehyde

. Beaker, 500 mL with a magnetic stirrer bar
. Magnetic stirrer
. Glass bottle for storage, 500 mL

Procedure
The breaker was filled with ethanol (370 mL); concentrated sulfuric acid
(14 mL) was added slowly followed by glacial acetic acid (4 mL) and then p-
anisaldehyde (1 mL). The solution was stirred for 15 minutes and then trans-
ferred to a suitable labelled bottle for storage.