372 CINNAMENE. 



SECOND GROUP. 



Cinnamene (StyroC). 

 C 8 H 8 = C 6 H 6 .CH:CH 2 . 



Is contained in liquid storax, the expressed viscid 

 juice of the bark of Liquidambar orientale ; and is ob- 

 tained from this by distilling with water and sodium 

 carbonate.. Is formed by heating benzene-ethyl bro- 

 mide (p. 285) with water or baryta, and by heating 

 acetylene gas (cf. Benzene). Is probably also con- 

 tained in coal-tar. Colorless, mobile liquid, of an 

 aromatic odor ; refracts light strongly. Boiling point, 

 146 ; specific gravity, 0.924. When kept it is slowly 

 converted into metacinnamene, a body polymeric with 

 it ; the same change takes place rapidly by heating it 

 to 200. Metacinnamene is a solid, amorphous, trans- 

 parent mass, which, when distilled, is reconverted into 

 cinnamene. Cinnamene yields benzoic acid when sub- 

 jected to the influence of oxidizing agents. 



Cinnamene chloride, C 8 H 8 C1 2 = C 6 H 5 .CHC1.CH 2 C1, 

 and Cinnamene bromide, C^^r 2 , are produced by 

 the direct combination of cinnamene with chlorine or 

 bromine. The chloride is liquid ; the bromide crys- 

 tallizes in colorless laminae or needles, that fuse at 67. 

 Heated alone, or, better, with caustic lime or alcoholic 

 potassa, these compounds are converted respectively 

 into a,-chlor cinnamene, C 6 H 5 .CH:CHC1, or a-bromcinna- 

 mene. Both of these latter compounds are heavy 

 liquids, not distillable without decomposition, the 

 vapor of which excites to tears. The isomeric substi- 

 tution-products, $-chlor cinnamene, C 6 H 5 .CC1:CH 2 (liquid, 

 boiling, without decomposition, at 199, of a pleasant 

 odor like that of hyacinthes), arid p-bromcinnamene, 

 C 6 H 5 ; CBr:CH 2 (boiling point, 228), are formed by 

 heating phenylchlor- and phenylbromlactic acids (pp. 

 354 and 355) with water at 200. 



Cinnamene iodide, C 8 H 8 I 2 , separates in crystals 

 when a solution of iodine in potassium iodide is added 



