bo 
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PROFESSOR LETTS ON PHOSPHORUS-BETAINES. 3: 
Action of Bromacetic Acid on Triethyl-Phosphine. 
A preliminary experiment showed that a very violent action occurs when 
the two bodies are mixed, so violent indeed that the greater part of the 
mixture was blown out of the vessel in which it was made. 
If, however, the two are mixed in the apparatus employed for preparing the 
hydrochlorate of triethyl-phosphorus-betaine (see p. 301) and with similar pre- 
cautions, the reaction is completely under control. 
The bromacetic acid is at first dissolved by the phosphine, and the mixture 
then grows very hot. If the phosphine is added slowly, and the mixture well 
agitated from time to time, a colourless syrupy liquid results, which does not 
solidify on standing. If, on the other hand, the phosphine is added rapidly, 
and the temperature has not been kept down, the product is dark brown in 
colour, and very often solidifies almost completely on standing. The colour- 
less syrupy product also solidifies on cooling if it be heated for a short 
time at 100° C., but it grows brown during the operation. The solidified 
product is extremely deliquescent, liquefying almost immediately when ex- 
posed to the air. It is very soluble in alcohol, but is insoluble in ether. 
The addition of the latter to its alcoholic soluticn causes the precipitation 
of an oily liquid which refuses to crystallise. It is also soluble in chloro- 
form, and ether often precipitates it from its solution in that liquid in the 
form of small rhombic crystals. It is, however, extremely difficult to recrys- 
tallise it in this way, and the brown colouring matter adheres to the crystals 
most obstinately. 
The properties of the product either before or after recrystallisation are not 
those of a salt of the phosphorised betaine. Thus it yields no crystalline 
compound with chloride of platinum, nor could a crystalline chloroplatinate be 
obtained after its bromine had been replaced by chlorine (by treating its solu- 
tion with oxide of silver, filtering and adding hydrochloric acid). 
It was found that its solution gave with carbonate or acetate of lead 
crystalline compounds, and much time was spent in endeavouring to fix their 
composition. 
On adding carbonate of lead to the aqueous solution of the product, 
effervescence occurs, and if the solution is hot, a crystalline precipitate is soon 
formed. Also on mixing acetate of lead with a solution of the product, sparingly 
soluble crystalline compounds are produced. If the solutions are cold a white 
flocculent precipitate falls, which in tolerably dilute solution dissolves spontane- 
ously. On scratching the sides of the vessel in which the two solutions have 
been mixed, or on warming the mixture, a colourless salt is precipitated in 
needles or plates. If the solutions are boiling two salts are often formed—one 
