The reaction of halogens with olefins containing a double bond in an unbranched carbon chain is changed from addition to substitution by operating at elevated temperatures. This substitution, unlike the induced reaction described in the first paper (4), occurs exclusively into the olefin with the formation principally of allyl-type unsaturated monohalides. The optimum temperature ranges from 300°to 600°C ., depending on the nature of the olefin and halogen.Operating conditions have been examined in some detail so that the work can serve as a basis which will make this class of products easily available.ALTHOUGH it is known that the reaction between /A chlorine and olefins containing a tertiary carbon atom at the double bond leads predominantly to chlorine substitution in the allyl position, the only observation of formation of allyl-type chlorides from straight-chain olefins is that of Stewart and Weidenbaum (9). These investigators found pentenyl chlorides in the chlorination product of 2-pentene, but only in small amounts. In general, the main chlorination product of straight-chain olefin is the di-
and eight-tenths grams of tetrakis(hydroxymethy1)phosphonium chloride dissolved in 100 cc. of water was boiled with 19 g. of barium hydroxide for several hours until the evolution of hydrogen ceased. The barium was then removed with a slight excess of sulfuric acid and the hydrochloric acid with silver carbonate. From the filtrate, dissolved silver was precipitated with hydrogen sulfide. The filtrate was then evaporated on the water-bath to a sirup and the heating continued for some time to drive off any formic acid which might have resulted from the action of barium hydroxide on formaldehyde. The acid was then converted into the barium salt by boiling with water and barium carbonate, the filtrate evaporated to small bulk and allowed to crystallize. The crystals were washed with a little water. The mother liquor seemed to contain caramel-like substances formed by the action of barium hydroxide on formaldehyde. The product consisted of well-developed crystals, moderately soluble in water, insoluble in alcohol.
Anal.Calcd. for CaHlzOsPzBa: Ba, 35.4; P, 16.02. Found: Ba, 35.2; P, 15.68.
SummaryThe action of alkali on tetrakis(hydroxymethy1)phosphonium chloride has been shown to take place in two stages, giving first tris(hydroxy-methy1)phosphonium oxide and finally bis(hydroxymethy1)phosphinic acid and liberating one molecule of hydrogen a t each stage. With a neutral carbonate the action stops a t the oxide stage.Tetrakis(chloromethy1)phosphonium chloride was prepared from the corresponding hydroxy derivative by treating with phosphorus pentachloride. This was converted into tris(chloromethy1)phosphine and the latter to tris(chloromethy1)phosphine oxide.A crystalline barium salt of bis(hydroxymethy1)phosphinic acid was obtained.The only organo thallium compounds known are of the type R2T1X,* i . e., salts of the bases RzTIOH first isolated by R. J. Meyer and A. Bertheim.2 Many alkyl and aryl compounds of this type have been prepared by attempted without success to prepare TIRI or ("1 (CzHd 2) 2.Hansen, Ber., 3, 3 (1870); Hartwig, ibid., 7, 298 (1874).
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