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Structure property relationships in polimers

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The mechanism postulated (605) is essentially that given before (600); it is noteworthy however that the detailed structure of the biguanide employed as reactant in methanol differs from that given in an earlier paper (602) by the same authors, thus introducing some inconsistency into the discussion of the detailed mechanism. The interaction of phenylbiguanide with ethyl r162 (but not with the corresponding chloro-ester) in methanol-sodium methoxide (600) yields phenylbiguanide hydrobromide in addition to the expected 2-(~-bromoethyl)-6-phenylguanamine (19%).

Kurzer a n d E. D, Pitchfork The ultraviolet spectra of a number of further biguanides, recorded during other investigations, are collected in Tables 6 and 7. Table 6. Ultraviolet absorption of biguanide derivatives /max m~ e Ref. 63 • 103 (74) 410 Ethanol The Chemistry of Biguanides Table 7. NH. 1 m~ Validity of Beer's Law In the colorimetric estimation of ~-pbenethylbiguanide the plot of readings against concentration is found (670) to be a straight line at concentrations less than 10-4M. Above this concentration, ~-phenethylbiguanide in solution deviates sharply from Beer's Law.

The reaction between 2-(~c-bromoethyl)-6-phenylguanamine and phenylbiguanide was carried out (486) in an unsuccessful attempt to obtain a vinyl-guanamine; phenylbiguanide hydrobromide, however, was recovered. b) Hydro~cy-Estcrs An anomalous reaction of the hydroxy-activated ester, ethyl lactate has also been noted (602). With ~-phcnethylbiguanide this gave, in addition to the expected guanamine (XCII), the corresponding hydroxy-compound (XCIII), but no chemical evidence for this formulation was given.

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