Pentamethylene Pentane

Acryloyl chloride (0.2 mole) in dry benzene (60 ml) was added over 0.5 hour to pentane-1,5-diol (0.1 mole), triehylamine (0.2 mole) and pyrogallol (0.1 g) in dry benzene (100 ml). Further dry benzene (100 ml) was added followed by triehylamine (10 ml), and the mixture stirred at 50°C for 0.5 hour. The triehylamine hydrochloride was filtered off and the solvent removed in vacuo to leave yellow oil which was distilled in the presence of a trace of p-methoxyphenol, excluding light, to give 1,5-pentamethylene diacrylate (12.9... 

Similar reactions between aluminum telluride and 1,5-dihalopentanes produced 5-halopentyl pentamethylene telluronium halides and pentane-1,5-diyl bis[pentamethylene telluronium] dihalides3. 

Sodium arenetellurolates, prepared by reduction of diaryl ditelluriums with sodium borohydride, reacted with 1,4-dichlorobutane, 1,4-dibromobutane , and 1,5-dibromo-pentane forming aryl tetra- or pentamethylene telluronium halides. 

All these compounds give the same products when treated witli bromine, iodine, or mercuric halides. With iodine in benzene solution theoretical yields of pentamethylene-dimercuri-iodide and di-iodo-pentane are obtained. 

Pentadiene and dialkyl alanes give addition products from which only pentane is split off on hydrolysis (88). Nothing further is known yet about the constitution of these compounds, e.g., if aluminum heterocycles (6- or 5-ring compounds) are formed. Tris(3,3-dimethyl-pentamethylene) dialane is said to be formed from 3,3-dimethyl-l,4-pentadiene and di-isobutylaluminum hydride in 98% yield, even under forcing conditions at elevated temperatures (160°C). The compound distills at low pressures (b.p.io-t 132°-140°C) (212). 

Complex Mixtures.—The separation of isopentane and normal pentane (b. p. 27-95° and 36-3° middle point 32-15°) from a mixture containing also butanes, hexanes and a very little pentamethylene has been already referred to (p. 138). Taking the weight of distillate between 27-95° and 36-3° as 100 in each case, the percentage coming over between 27-95° and 32-15° became roughly constant after... 

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