140 PROCEEDINGS OP THE AMERICAN ACADEMY 



takes place in an entirely analogous manner, and on distilling 

 benz-o-toluide (mpt. 142°) is obtained as the cbief product. 



Molecular Rearrangement. — The conversion of o-tolylisocyanide 

 into o-tolylcyanide* takes place quantitatively on heating 4 c.c. of 

 the former in a sealed tube for three hours at 235°-245° (at 180°- 

 200° no change whatever takes place). 3 grams of o-tolylcyanide 

 were obtained, boiling at 202° -203° (thermometer entirely in the 

 vapor) at 728 mm. ; and from this, by saponification with sulphuric 

 acid, | o-toluylic acid melting at 104°. 



Tbis molecular rearrangement has already been noticed by 

 Weith, j in the case of an o-tolylisocyanide containing o-toluidine. 

 Weith was in fact the first to prove that the alkylisocyanides, 

 KNC, go over by molecular rearrangement into the corresponding 

 alkylcyanides, HOIS". Gautier states, in a preliminary paper, § that 

 the boiling point of methyl and ethylisocyanide is raised after some 

 standing, and thinks that this is to be explained by a partial con- 

 version into methyl and ethylcyanide. In bis last paper || on the 

 isonitriles he says nothing whatever about this supposed molecular 

 rearrangement, but states that on long heating of methyl and 

 ethylisocyanide in sealed tubes at 200°, a portion polymerizes, but 

 tbat much unchanged isonitrile is left. A molecular rearrange- 

 ment in the case of the isonitriles has therefore only been proved 

 in the case of phenyl- and of o-tolylisocyanide. 1T 



Action of Primary Amines. — 4 grains o-tolylisocyanide were 

 heated with reversed condenser with 4.4 grams o-toluidine for forty 

 minutes at 190°-220°. On cooling, no isonitrile smell was left, 

 and the dark brown solid residue was recrystallized four times from 

 alcohol; thus 2.2 grams perfectly pure o-ditolylformamidine,** 

 melting point 151°, were obtained. 



0.2033 gram substance, dried at 110°, gave 22.5 c.c. moist nitro- 

 gen at 16° and 748 mm. 



Theory for C 15 H l6 N 2 . Found. 



N 12.50 12.69 



* Cf. Weith, Ber. d. chem. Ges., VII. 722. 

 t Cahn, Ann. Chem. (Liebig), CCXL. 280. 

 \ Ber. d. chem. Ges., VII. 722. 



§ Comptes Rendus, LXV. 862; Ann. Chem. (Liebig), CXLVI. 128. 

 || Loc. cit., XVII. 226. 



T Compare the discussion of Weith and Hofmann on this subject in Ber. d. 

 chem. Ges., VII. 722, 814, 1017, 1021. 

 ** Ladenburg, Ber. d. chem. Ges., X. 1260. 



