J-Limonene

Scheme 56 summarizes Mori s synthesis of (S)-vesperal (38), the female sex pheromone of the longhorn beetle (Vesperus xatarti) [85]. (J )-Limonene yielded (S)-38 by utilizing organoselenium chemistry. 

The following protocols are primarily conducted to ensure the quality of citrus oils during various phases of citrus processing. Citrus processors must account for quality and quantity of citrus oils sold to flavor houses. This not only includes monitoring recovered oils (i.e., cold-pressed oil, essence oil, and J-limonene) but also the total available oil. 

Basic Protocol 7 was developed to estimate the mass balance of J-limonene within a citrus processing plant. However, the calculations must be normalized to provide a basis of comparison. This is achieved by determining the moisture content of those samples. Samples are dried at low temperatures under a vacuum. This removes the moisture in the sample and prevents any decomposition of the remaining solid matter. 

Several trial compounds may have to be made before a reasonably close analytical match is obtained. One of the problems that arises at this stage is sorting out the contribution that various components can make to the total quantity of a single ingredient found in the analysis. If citronellol is present, it may be because it occurs as a specified component in the formula, because it comes from a number of different essential oils, or because it is included in one or more bases. Many of the terpenes, such as J-limonene, are present in numerous essential oils, any number of which may be present. Trying to get back to the original formula requires considerable deductive powers and ingenuity on the part of the perfumer. 

All compounds produced an increase in the renal content of a2u-g for d-limonene, the protein was increased 2- to 2.75-fold over the dose range following 14 doses over 21 days. With decalin, the maximum increase was 4-fold however, the control value was very low and was not in line with the previous data or with that expected in mature adult male rat kidneys. For PGMBE, again the control value was low with the maximum increase being about 2.25-fold. For SS IIC, the increase was 1.5- to 2-fold over the dose range after 3 months of exposure. The quantitation of hyaline droplet accumulation showed a dose-related increase with these chemicals with a severity band of 2 for the controls and 3-4 for the treated animals. For d-limonene, the severity band was 2-3, the lower response presumably reflecting the shorter duration of exposure. Thus J-limonene and decalin showed a more marked... 

Hills, H. G., Fragrance cycling in Stanhopea pulla (Orchidaceae, Stanhopeinae) and identification of rra j-limonene oxide as a major fragrance component, Lindleyana, 4, 61-67 (1989). 

In the first enantioselective synthesis of triquinane (-)-cucumin H 168 [38], a quaternary center is introduced via an orthoester rearrangement. AUylic alcohol 170 is prepared from (J )-limonene 169 by a known sequence of reactions. Orthoester rearrangement occurred in a highly stereoselective manner anti to the iso-propylidene side chain and afforded ester 171. Then diazoketone cycUzation followed by cationic cyclization gave rise to the desired tricyclic system (Scheme 6.25). 

Nielsen, T.J., Limonene and Mircene Sorption into Reflllable Polyethylene Terephtha-late, and Washing Effects on Removal of Sorbed Compounds, J. Food Sci., 59, (1), 227, 1994. 

The chiral leaving group-Lewis acid combined system is also effective for the enantioselective synthesis of carbocyclic compounds which have the basic structure of terpenes without possessing remarkable functionalized groups [63]. They successfully applied this method to produce (+)-(J )-limonene from the corresponding allylic ether in two steps, obtaining an overall yield of 77%. (Scheme 10.38). 

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