254
NOTE ON T H E ACTION OF "LI.COIIOI,IC POTASII.
NOTE ON THE ACTION O F AL('O1IOLIC POTASH ON IIEPTYLEK'E BROhfIDE.
F. 1'
\-ENAHIE,
PEI. n.,
Having on hand a s d l supply of heptylene bromide, described in this journal (IT.22), t h e avtiori of an alcoholic solution of potassium hydrate was tried upon it v it11 a view to the formation of a hydrocarbon with two less carbon atoms a heptine isomeric with the oenanthylidene of Lirnpricht (Liebig's Annalen 103.81) and the tetra niethylallylene of Henry (Ber. Chem. Ges 8. 400). These two bodies were formed by t h e action of alcoholic potash on the chlorides It was interesting then to bee if the rcactioii with this bromide would follow the same eour From sewn to eight grammes of heptglene bromide were placed in a flask and an excehh of a stronq alcoliolic solutioii of c~anstic potash added ( 2 mol KOH to I mol C,II14Br2being the proportion required by formula). T o condense and return the alcohol to the flask it was connected with an upriglit condenwr. Tlic reaction commenced immediately irt the cold-potassium bromide begitiiiirig t o deposit-but it went on very slowly without the :Lid of heat. accordingly heated 1-6 hours 011 a water bath, the potassium salt forming R tliick clepo'it on the sides of the fla-k and the liquid, at first colorles3, darkening to a reddish b l x k . A t the expiration of this time no furtlirir precipitation of potassium bromide was observable oti adding fresh nlcoliolie pota.11. Tlie oily liquid was thoroughly waslied with water, heparatirig i n a lighter layer at the top of the separating frinnel, was dried over calciiun chloride and finally fractioned under 100°C , the amount corning over was small. The thermometer the rose rapidly to 150°C'. then blowly to 160°C. Betwecn these two dcgiees 1iear1y tlie whole product came over, leaving a clirt?;, tliick mas- behind in the fractioning flask. On redi5tillirig the fraction from 15~)o-16(~0Ci,R srnall portion of a constant-boiling product was ol~taine(l-boiling a t 156"158°C. This was immediately sealed in a tube and Yet aside for analysis On examining it qualitatively, brorriine v a s found Ire$ent i n considerable amount h o that clearly some brominatect compound instead of the expected C,IIi2had lwen formed 11) the reaction, Seeing that Bruylaut (Ber. Chein (h51. 40!1) had prepared a moncbromcenanthylene by tlie actioti of alcoholic potash on oenanthylene bromide (heated tugether t w o days in closed tubes), a
ANALYSIS OF ROCK-SALT.
255
bromine determination was made after the method of Carius to see if some similar body had not been found in this case. A confirmatory determination would have been made but unfortunately part of the liquid was lost. 0.1895 grm. substance gave 0.2019 grm. silver bromide. Calculated for C,Hl,13r, 45.19 per cent. Br-found 45.34 per cent. Probably the first small fraction coming over somewhat under 100° consisted of C',H>, but the quantity was too small for examination and purification. The reaction then, instead of following the formula, C,H,,Br,2KOH=C,H1~+K~r+2II,O was rather C,H,,Br,+ KOH=C,H,,Br+KBr+H,O in spite of the excess of alcoholic potash, Bromheptylene-C,H,,Br is a colorless mobile liquid, with a pleasant though pungent aromatic odor, lighter than water and boiling at 156"-158OC. The two bodies C,H,,Br, and C,Hl,, prepared by Bruylaut had respectively the boiling points 165°C and 100°C. This gives a difference of 7"-9" in boiling points between the derivation from the cenanthal heptane and the Pinus Sabiniana heptane. Nearly the same difference is noticed between the heptylic bromides C,H,,Br from oenanthal boiling at 178.5" and from P. Sabiniana boiling at 165.5." University of North Carolina.
NOTES FROM T H E CHENICAL LABORATORY O F T H E UNIVERSITY O F N O R T H CAROLINA-ANALYSI? OF ROCK-SALT FROM SALTVILLE, WASHIKGTON C O., VA. B Y THObfAS
RADCLIFFE.
A specimen of this rock-salt sent by the superintendent of the salt-works i n the valley of the Holston, yielded on analysis some. what different results from the previously published analysis (Chem News No. 1038) and in view of this and the claim made for this Virginia brine, that it exceeds in purity nearly all others of which analyses are on record, the analysis made in this laboratory is published. The Fpecimen was brownish-red in color, with a crystalline structure and was obtained whilst deepening one of the salt-wells. This rock-salt is not mined, the brine alone being used for the manufacture of salt. The capacity of the works is at present 450,000
