122 



loss than Burgess appears to accept, — a matter which is of con- 

 siderable importance, in view of the low citral-content of the oils in 

 question. We will return to this method when the opportunity arises. 



Camphor. In several treatises J. W. Bruhl 1 ) provides contri- 

 butions to the knowledge of the halogen derivatives of camphor. If 

 oxymethylene camphor in alkaline solution is iodised, no camphor 

 mono-iodide is formed, but a di-iodo-substitution product. In neutral 

 solution iodo-formyl camphor, or iodo-camphoric aldehyde is formed, 

 which when submitted to the action of alkali and iodine, is converted 

 into the above o, o-di-iodo camphor. The latter, when treated with 

 methyl alcoholic potash, with the application of heat, yields o-mono- 

 iodo camphor. The last-named body is also formed when dilute 

 sodium methylate, with application of heat, is allowed to act on iodo- 

 formyl camphor. O-iodo camphor 



/HI 



x CO 

 forms colourless prisms melting at 42 ° to 43 °. O, o-di-iodo camphor 



C 8 H / I 



>co 



entirely resembles in its appearance iodoform. It melts at io8°to 109 . 

 Iodo-formyl camphor 



XI— CHO 

 C 8 H / I 



crystallises in leaflets of the melting point 67 to 68°. It is fairly readily 

 decomposed. O-iodo camphor is also formed from o-bromo camphor, 

 if iodine is allowed to act on the latter's magnesium compound: 



.CH-MgBr XH-I 



C S H 14 < I + I 2 = C 8 H / I +MgBrI 



7 CHBr 

 C 8 H U <I +Mg = 



further, from camphor, sodium amide, and iodine: 



CHI 



C 10 H 16 O + NaNH 2 = NH 3 + 



C 10 H 15 NaO + I 2 = Nal+ C^H, / I 



CO; 

 and finally from camphor, sodium, and iodine: 



C 10 H 16 O + Na = H + 



y CHI 

 C 10 H 15 NaO + I 2 ^ NaI+C 8 H 14 <( I 



In iodo-formyl camphor, both the formyl-group and the iodine 

 atom can be readily substituted by hydrogen. Up to the present, 



J ) Berl. Berichte 37 (1904), 2156, 2163, 2178. 



