454 M. Neuhoff on Naphthendichlorhydrine. 



engagement of gas, while in the residue remains carbonate mixed 

 with unchanged benzenate and with charcoal. 



This experiment could hitherto only be made on a small scale, 

 but it appears probable that the hydrocarbon mentioned above 

 is a new member of the homologous series &„ H 2 „_6. It has the 

 composition C 5 H 4 ; and to express this fact, and also its con- 

 nexion with the benzole series, Carius names it Pentole. Its 

 formation from benzenic acid may be thus expressed : 



C 6 H 4 2 = GO 2 + G 5 H 4 . 

 Benzenic acid. Pentole. 



Neuhoff has described the preparation of a new tetratomic 

 alcohol derived from naphthaline*. "When this latter substance is 

 treated with hypochlorous acid, combination ensues, with forma- 

 tion of a new substance which the author calls Naphthendichlor- 

 hydrine. Thus : 



€ 10 H 8 + 2ClHO=G 10 H ,0 Cl 2 O 9 . 



Naphthaline. Naphthendichlorhydrine. 



It is a clear yellow substance crystallizing in distinctly formed 

 prisms ; it melts at a gentle heat to an oily liquid, and is decom- 

 posed at a higher temperature. It is but little soluble in water, 

 but readily so in alcohol and ether. It is easily decomposed by 

 alkalies, in accordance with the equation 



€ 10 H 10 Cl 2 O 2 + 2KHO=2KCl-f-€ 10 H 12 O 4 . 



The new body here is a tetratomic alcohol, „ 4 WO 4 , and is 



called naphthenic alcohol. It is probably colourless, but rapidly 

 becomes brown ; it crystallizes in distinctly formed prisms, melts 

 at a gentle heat, and cannot be distilled without decomposition. 

 It is not soluble in water, but readily so in alcohol and in ether. 

 The alcohol forms metallic compounds in which four atoms of 

 hydrogen in its molecule are replaced by metals; these com- 

 pounds, however, are difficult to obtain pure. 



When naphthenalcohol is treated with very dilute nitric acid 

 on the water-bath, it gradually dissolves, becoming oxidized, 

 The clear yellow solution yields, after all nitric acid has been 

 removed by repeated evaporation, a pale-yellow acid crystallizing 

 in prisms. This acid the author calls naphthoxalic acid; it has 

 the composition € 10 H 8 O 6 , and stands to naphthenalcohol in the 

 same relation as oxalic acid to glycol. It is formed in accord- 

 ance with the following equation, 



€, °h!}o 4 +O 4 = €10H4 ^ V }o 4 + 2H 2 O. 



Naphthenalcohol. Naphthoxalic acid. 



* Liebig's Annalen, December 1865. 



