Petroleum ligroin

The cyclized product usually precipitates from the reaction mixture in crystalline form at room temperature. The precipitation of the product may be completed by adding light petroleum, ligroin, or hexane to the reaction mixture (e.g., 51JOC1414 56BRP743901, 56JCS3079). 

Alkylation and arylation of organosilanes occur readily with alkyl and aryl alkaU metal compounds. Yields from these reactions are good but are iafluenced by steric requirements on both silane and metal compounds. There is Httie iaductive effect by the organic groups attached to siUcon, as measured by the yield of products (126,127). These reactions proceed more readily ia tetrahydrofuran and ethyl ether than ia ligroin or petroleum ether, where R and are alkyl or aryl and M is Li, Na, or K. 

To 16.3 g Na in 210 ml ethanol add 93 g ethyl-acetoacetate (ethyl-3-oxo-butanoate), heat to boil and add dropwise 92 g (II) over 20 minutes. Stir and reflux five hours and cool to precipitate. Filter, wash with ethanol and dissolve precipitate in 800 ml water. Cool to 0° C and slowly add 80 ml ice cold concentrated HC1 to precipitate. Filter, wash with water and ligroin to get about 108 g 6-carbethoxy-4,5-dihydro-olivetol (ID) (reciystallize from petroleum ether). To 104 g (III) in 260 ml glacial acetic acid at room temperature with good stirring, add dropwise over one hour 69 ml Bromine. Heat-four to five hours at 60° C, cool and add 300 ml water and let stand twelve hours. Oil separates which will precipitate on agitation and... 

Use a hydrocarbon solvent (hexane, ligroin, petroleum ether—and no flames ) to dissolve the oil that s left. 

The petroleum ether solvents are a specific-boiling-range naphtha, as is ligroin. Thus, the term petroleum solvent describes a special liquid hydrocarbon fraction obtained from naphtha and used in industrial processes and formulations (Weissermel and Arpe, 1978). These fractions are also referred to as industrial naphtha. Other solvents include white spirit, which is subdivided into industrial spirit [distilling between 30 and 200°C (86 to 392°F)] and white spirit [light oil with a distillation range of 135 to 200°C (275 to 392°F)]. The special value of naphtha as a solvent lies in its stability and purity. 

Ligroine (ligroin) a saturated petroleum naphtha boiling in the range 20 to 135°C (68 to 275°F) and suitable for general use as a solvent also called benzine or petroleum ether. 

Petroleum ether (ligroin) Unknown 1 Strong adds Concentrated S... 

Soluble in benzene, ether, ligroin (Weast, petroleum ether (Windholz et al, 1983)... 

This property can be used to separate highly volatile and low-viscous mineral oils from oil-water dispersions.To demonstrate this,a dispersion of 20 ml of ligroin or petroleum ether in 200 ml of water is prepared in a 400 ml beaker with a fast-running mixer.Then approx. 5 g of crushed urea/formaldehyde foam are added. After 5 min the solution is filtered through a folded filter.The aqueous filtrates are optically free from dispersed hydrocarbons. In the same way a crude oil/water dispersion can be separated. 

To save space the following abbreviations have been generally used in Chapters 3, 4 and 5 abs (absolute), anhyd (anhydrous), aq (aqueous), atm (atmospheric), crystd (crystallised), crystn (crystallisation), crysts (crystallises), dec (decomposes), dil (dilute), distd (distilled), distn (distillation), evap (evaporate), evapd (evaporated), evapn (evaporation), filtd (filtered), h (hour[s]), pet ether (petroleum ether, ligroin), ppte (precipitate), ppted (precipitated), pptn (precipitation), satd (saturated), soln (solution), TLC (thin layer chromatography), HPLC (high pressure liquid chromatography), vac (vacuum), vol (volume). Other abbreviations used occasionally are self evident in meaning. 

Though safer than the decomposition of pure, solid diazonium tetrafluoroborates, dediazoni-ation of these compounds mixed with inert solid salts cannot be scaled up to a large extent since heat exchange through large quantities of powdered solids rapidly becomes difficult. Thus, dediazoniation of arenediazonium tetrafluoroborates suspended in inert fluids is an alternative proposition.13105 141 175-219 220 In addition to the safety improvement, lower quantities of tar are formed using this technique. The inert fluid can be ligroin,143 petroleum ether,147 Decalin,3 or simple aromatic compounds,1-3,5,131-221 such as toluene, xylene, biphenyl, nitrobenzene,177 or quinoline. Simple esters have also been used as solvents in the dediazoniation... 

Lassaigne test, 1039, 1040 defects in, 1043 Lead dioxide, 199 Lead tetracetate, 199, 951 Lessing rings, 92 Leuckart reaction, 561, 567 Liebermann nitroso reaction, 649 Light petroleum, purification of, 174 Ligroin, 174 Linseed oil, 445... 

The acid chloride is dissolved by refluxing with 500 ml. of 90-100° ligroin, and the hot solution is decanted from the sodium carbonate onto a fluted filter. This process is repeated with three 150-ml. portions of ligroin. The combined filtrates are concentrated to 500 ml., filtered if necessary, and cooled to 0°. The acid chloride is collected on a Buchner funnel and pressed as dry as possible. It is washed twice with 30-60° petroleum ether and stored in a vacuum desiccator over phosphorus pentoxide and paraffin shavings (Note 6). The yield of orange-red crystals melting at 94.5-95.5° is 48 g. (89%). 

Also known as petroleum ether and sometimes termed ligroin when referring to fractions of b.p. above 100 C. 

Benzine an obsolete term for light petroleum distillates covering the gasoline and naphtha range see Ligroine. 

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