Ber 1914 pages 71-72 German to English translation.
Alpha, beta- hydrocinnamic acid
The hydrogenation was carried out according to Paal-Skita. The cinnamic acid was just neutralized with alkali, after addition of several cubic
centimeters of colloidal palladium solution hydrogen under 1 atm. pressure was led in, until a probe (in Soda solution) of permanganate was no longer
reduced. Both forms of the cinnamic acid gave the same hydro derivative.
The hydro acid forms beautiful, white, surface rich crystals, which when recrystallized from gasoline melt at 137-138°. After further
recrystallization the melting point sank to 132°, whereby from the prisms broad, white needles were obtained. After further recrystallizations we
found the melting point always to be 130-131.5°. The substance was already soft before this.
Reduction with sodium amalgam. In the cold or at room temperature the sodium amalgam had over all no effect on the dimethylcinnamic acid. Although, 1
g of the acid could be fully reduced with 3 % amalgam through long warming and shaking on a water bath, whereby 50 times excess of amalgam was
necessary. The hydro acid melted at 137-138° and was certainly identical with that described above, although the melting point after
recrystallization was not undertaken.
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