Terpinen

By oxidation with permanganate it forms pinonic acid, C,oH,<503, a monobasic acid derived from cyclobutane. With strong sulphuric acid it forms a mixture of limonene, dipentene, terpinolene, terpinene, camphene and p-cymene. Hydrogen chloride reacts with turpentine oil to give CioHijCl, bomyl chloride, artificial camphor . 

In a chromatographic analysis of lemon oil a peak for limonene has a retention time of 8.36 min with a baseline width of 0.96 min. y-Terpinene elutes at 9.54 min, with a baseline width of 0.64 min. What is the resolution between the two peaks ... 

Terpenes, specifically monoterpenes, are naturally occurring monomers that are usually obtained as by-products of the paper and citms industries. Monoterpenes that are typically employed in hydrocarbon resins are shown in Figure 2. Optically active tf-limonene is obtained from various natural oils, particularly citms oils (81). a and P-pinenes are obtained from sulfate turpentine produced in the kraft (sulfate) pulping process. Southeastern U.S. sulfate turpentine contains approximately 60—70 wt % a-pinene and 20—25 wt % P-pinene (see Terpenoids). Dipentene, which is a complex mixture of if,/-Hmonene, a- and P-pheUandrene, a- and y-terpinene, and terpinolene, is also obtained from the processing of sulfate Hquor (82). 

Chemical Designations - Synonyms Limonene para-Mentha-1,8-diene Phellandrene Terpinene delta-1,8-Terpodiene Chemcal Formula CjoH]j. 

Determination of the enantiomeric distribution of a-pinene, /3-pinene, limonene, terpinen-4-ol and nerolidol in neroli and petitgrain oils... 

Mondello et al. (2, 20-23) have used a multidimensional gas chromatographic system based on the use of mechanical valves which were stable at high temperatures developed in their laboratory for the determination of the enantiomeric distribution of monoterpene hydrocarbons (/3-pinene, sabinene and limonene) and monoterpene alcohols (linalol, terpinen-4-ol and a-terpineol) of citrus oils (lemon, mandarin, lime and bergamot). Linalyl acetate was also studied in bergamot oil. The system consisted of two Shimadzu Model 17 gas chromatographs, a six-port two-position valve and a hot transfer line. The system made it possible to carry out fully... 

Tbe oil contains a considerable amount of tni-pinyl acetate ( therefore requires at least two hours for complete saponification), terpineol was identified as d-a-terpiucol by ficbimmel A- Co, The pene terpinene has been stated to be present, hut this is not conhri by the author, nor hv Schimmel A Co. Limoneue is probably pre iu atnall amount. Free terpineol is also present. 

Ser coni, of linalol is indicaled, Jjf,ilni.a-fi ueue. i-a-pinene, /J.pincne, ipentene, eymcnc, terpinene, getaniol, bornc.ol, acetic esters, and decyl aldehyde are also presfut in the oil. with, possibly, phcllandrene and tcrpinoleue. 

By the action of hydrochloric acid gas on sabinene dissolved in acetic acid, terpinene dihydrochloride is produced, melting at 52°. If no trace of moisture is present the monohydrochloride alone is yielded. 

Considerable difference of opinion exists as to the relationships of sabinene to terpinene, and the conversion of sabinene into terpinene hydrochloride is to be explained by a molecular rearrangement, and cannot be said to be evidence of relationship. ... 

Semmler then suggested that ortho-limonene might be ordinary limo-nene, and that dipentene had the psendo-formula, and that both these compounds would yield identical halogen derivatives with the breaking of the double linkage. He subsequently modified his view to some extent and considered that terpinene was represented by the pseudo-limonene formula. 

---