Hydrocarbons monoterpenic

Table 2. Properties of Selected Monoterpene Hydrocarbons and Ethers...

Wood is the raw material of the naval stores iadustry (77). Naval stores, so named because of their importance to the wooden ships of past centuries, consist of rosin (diterpene resin acids), turpentine (monoterpene hydrocarbons), and associated chemicals derived from pine (see Terpenoids). These were obtained by wounding the tree to yield pine gum, but the high labor costs have substantially reduced this production in the United States. Another source of rosin and turpentine is through extraction of old pine stumps, but this is a nonrenewable resource and this iadustry is in decline. The most important source of naval stores is spent sulfate pulpiag Hquors from kraft pulpiag of pine. In 1995, U.S. production of rosin from all sources was estimated at under 300,000 metric tons and of turpentine at 70,000 metric tons. Distillation of tall oil provides, in addition to rosin, nearly 128,000 metric tons of tall oil fatty acids annually (78). 

Elimination of water with the aid of sulfunc acid [9 14] and formation of the corresponding monoterpene hydrocarbons... 

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... 

Figure 10.3 Gas cliromatograms of a cold-pressed lemon oil obtained (a) with an SE-52 column in the stand-by position and (b) with the same column showing the five heart-cuts (c) shows the GC-GC chiral chromatogram of the ti ansfeired components. The asterisks in (b) indicate electric spikes coming from the valve switcliing. The conditions were as follows SE-52 pre-column, 30 m, 0.32 mm i.d., 0.40 - 0.45 p.m film tliickness cairier gas He, 90 KPa (stand-by position) and 170 KPa (cut position) oven temperature, 45 °C (6 min)-240 °C at 2 °C/min diethyl-tert-butyl-/3-cyclodextrin column, 25 m X 0.25 mm i.d., 0.25 p.m film thickness cairier gas He, 110 KPa (stand-by position) and 5 KPa (cut position) oven temperature, 45 °C (6 min), rising to 90 °C (10 min) at 2 °C/min, and then to 230 °C at 2 °C/min. Reprinted from Journal of High Resolution Chromatography, 22, L. Mondello et al, Multidimensional capillary GC-GC for the analysis of real complex samples. Part IV. Enantiomeric distribution of monoterpene hydrocarbons and monoterpene alcohols of lemon oils , pp. 350-356, 1999, with permission from Wiley-VCH.

L. Mondello, A. Verzera, P. Previti, F. Crispo and G. Dugo, Multidimensional capillar y GC-GC for the analysis of real complex samples. Part V. Enantiomeric distribution of monoterpene hydrocarbons, monoterpene alcohols and linalyl acetate of bergamot (Citrus bergamia Risso et Poiteau) oils , 7. Agric. Food Chem. 46 4275-4282 (1998). 

One consequence of the shift from grassland to shrubland is the potential for significant increases in volatile hydrocarbons added to the atmosphere. The leaves of creosotebush, Larrea tridentata, yielded 0.1 to 0.2 percent of a complex mixture of volatile compounds. That mixture contains several hundred compounds of which 100 accounted for more than 90% of the total volatiles (23). The volatiles that were identified included four monoterpene hydrocarbons, four oxygenated monoterpenes, six sesquiterpene hydrocarbons, eight aromatics like benzyl acetate and ethyl benzoate, plus... 

Monoterpenes lb 448 Monoterpene glucosides la 327,328 Monoterpene hydrocarbons la 76 Monoterpene ketones lb 252-254 Monuron lb 252,418 Morazone la 45 Morgan-Elson reagent lb 63 Morin la 44,91... 

Monoterpene glycosides 327, 328 Monoterpene hydrocarbons 76 Morazone 45 Morin... 

Geraniol, nerol and linalool are practically insoluble in water at ambient temperature. Although acid labile, they do not readily react in water at moderate temperature and neutral pH. In unacidified water at 220 °C in the MBR, they reacted within minutes. Geraniol rearranged to a-terpineol (18%) and linalool (16%) predominantly. Lesser amounts of the monoterpene hydrocarbons were also obtained, including myrcene, a-terpinene (10%), limonene (11%), y-terpinene, the ocimenes, a-terpino-lene and alloocimenes (Scheme 2.14) [50],... 

Winer, A.M., Lloyd, A.C., Damall, KR., Pitts, Jr., J.N. (1976) Relative rate constants for the reaction of the hydroxyl radical with selected ketones, chloroethenes, and monoterpene hydrocarbons. J. Phys. Chem. 80, 1635-1639. 

Whereas some species oxidize host terpenes more randomly, producing an array of rather unspecific volatiles with little information, others use highly selective enzyme systems for the production of unique olfactory signals. However, apart from transformations of monoterpene hydrocarbons of host trees, oxygenated monoterpenes may well be biosynthesized de novo by the beetles (see below). 

Figure 11.3 Stereoselective halo-hydroxylation of the monoterpene hydrocarbon (IS)-(+)-3-carene by CPO in the presence of hydrogen peroxide and halide ions (X — CC, Br or C).

Grimsrud, E. P., H. H. Westberg, and R. A. Rasmussen. Atmospheric reactivity of monoterpene hydrocarbons, NOs photooxidation and ozonolysis. Int. J. Chem. Kinet. Symp. 1 (Chemical Kinetics Data for the Lower and Upper Atmosphere) 183-195, 1975. 

TABLE 3-14 Photoxidation and Ozonolysis Rates of Monoterpene Hydrocarbons"... 

As in the case of the cyclic monoterpene hydrocarbons, a number of the cyclic sesquiterpenes are used as starting materials in the synthesis of fragrance and flavor substances or for the reconstitution of essential oils. 

In addition to monoterpene hydrocarbons, this oil contains up to 35% 1,8-cineole. 

Citrus oils contain up to 95% monoterpene hydrocarbons (usually limonene, but others as well, e.g., lemon oil also contains a-terpinene and /3-pinene). The important aroma-determining components of citrus oils are functionalized terpenes and aliphatic compounds (predominantly carbonyl compounds and esters), present only in relatively low concentrations [358]. Thus, several methods are employed to concentrate citrus oils on an industrial scale. The monoterpene hydrocarbon... 

In addition to 75% monoterpene hydrocarbons (Oa-pinene 5-21% /7-pinene 40-70% 3-carene 2-16%) and ca. 10% sesquiterpene hydrocarbons, galbanum oil contains a fairly large number of terpene and sesquiterpene alcohols and their acetates. Minor components, with entirely different structures and low odor threshold values, contribute strongly to the characteristic odor [284a, 515-519]. Examples are as follows ... 

The slightly turpentine-like odor and the relatively low solubility of the oil are caused by its high content of a-pinene and other monoterpene hydrocarbons. The main oxygen-containing component is l-terpinen-4-ol [551-556]. 

Other odoriferous materials are derived from the leaves and young twigs of Cistus ladaniferus. Cistus oil is obtained by steam distillation solvent extraction yields cistus concrete. Cistus oil, in contrast to labdanum oil, consists mainly of monoterpene hydrocarbons. 

Various qualities are commercially available. Their compositions may vary considerably because they are prepared from the resins of different Boswellia species. Main constituents of the oil are monoterpene hydrocarbons [284a, 658-661a]. 

The oil consists mainly of monoterpene hydrocarbons. Its main constituent is 1,3,8-menthatriene [18368-95-1], which is important for the aroma of parsley leaves [679-688]. 

The oil contains mainly monoterpene hydrocarbons (ca. 80%), its main constituent being sabinene [3387-41-5] (20-25%) [697-700c],... 

Pinaceae needle oils from Pinaceae species contain (—)-bornyl acetate as their main odoriferous component. Other main constituents are monoterpene hydrocarbons such as a- and /3-pinene, limonene, 3-carene, and a- and /3-phellandrene [713-718b]. The oils are used in perfumes for soap, bath products, and air fresheners and in pharmaceutical preparations. 

Monoterpene hydrocarbons, limonene (40-72), a-pheUandrene (10-24) and sesquiterpene alcohol elemol (1-25)... 

Juniper berry Juniperus communis L. Monoterpene hydrocarbons, pinenes, sabinene, myrcene... 

Nutmeg Myristica fragrans Houtt. Monoterpene hydrocarbons, sabinene, pinenes... 

Pepper Piper nigrum L. Monoterpene hydrocarbons (about 80), sabinene (20-25)... 

Sweet orange Citrus sinensis Monoterpene hydrocarbon. 

Galbanum Ferula galbaniflua Boiss., F. rubricaulis Boiss. 2-Methoxy-3-isobutyl pyrazine, 5-sec-butyl-3-methyl-2-butenethioate, 1,3,5-undecatriene as minor components, and monoterpene hydrocarbons (75), sesquiterpene hydrocarbons (10), lactones umbeUic acid, umbeUiferone... 

Monoterpenes hydrocarbons, such as sabinene [77, 78], terpinenes [12, 31, 32, 79, 80] and limonene [30, 73, 81-83], have also shown antimicrobial properties that appear to have strong to moderate antibacterial activity against Gram-... 

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