Terpene hydrate

Trihalomethane (ppb) Peak Area solution of terpene hydrate in a 25-mL volumetric flask and... 

After heating to 50 °C in a water bath, the sample was cooled to below room temperature and filtered. The residue was washed with two 5-mL portions of CCI4, and the combined filtrates were collected in a 25-mL volumetric flask. After adding 2.00 mL of the internal standard solution, the contents of the flask were diluted to volume with CCI4. Analysis of an approximately 2- tL sample gave LfD signals of f3.5 for the terpene hydrate and 24.9 for the camphor. Report the %w/w camphor in the analgesic ointment. 

Terpene hydrate—CioHi<,HaO—formed by distilling terpin with HCl or by allowing French oil of turpentine to remain for some days in contact with alcohol and HjSOt. It is an oily liquid, boils at 210°-214° (410°-117°.2 P.), suffering partial decomposition. 

Terpineol, an alcohol also prepared from turpentine oil by the action of sulphuric acid, terpene hydrate being formed as an intermediate substance. It has a distinctly characteristic lilac odour, and on account of its cheapness is much, used in soap perfumery, especially for a lilac or lily soap. Its specific gravity at 15° C. is 0 936-0 940 refractive index at 20° C., 1 4812-1 4835 and boiling point about 210°-212° C. It is optically inactive, and readily soluble in 1 5 volumes of 70 per cent, alcohol. 

Over the years, the term gums has been used to denote a wide range of compounds including polysaccharides, terpenes, proteins, and synthetic polymers. In the 1990s, the term more specifically denotes a group of industrially useful polysaccharides or their derivatives that hydrate in hot or cold water to form viscous solutions, dispersions, or gels (1). 

Uses ndReactions. a-Pinene (8) is useful for synthesizing a wide variety of terpenoids. Hydration to pine oil, acid-catalyzed isomerization to camphene, thermal isomerization to ocimene and aHoocimene, and polymerization to terpene resins are some of its direct uses. Manufacture of linalool, nerol, and geraniol has become an economically important use of a-pinene. 

Principal terpene alcohol components of piae oils are a-terpiueol, y-terpiueol, P-terpiueol, a-fenchol, bomeol, terpiuen-l-ol, and terpiaen-4-ol. The ethers, 1,4- and 1,8-ciaeole, are also formed by cycli2ation of the p-v( enthane-1,4- and 1,8-diols. The bicycHc alcohols, a-fenchol [512-13-0] (61) and bomeol (62), are also formed by the Wagner-Meerweiu rearrangement of the piaanyl carbonium ion and subsequent hydration. Bomeol is i7(9-l,7,7-trimethylbicyclo[2.2.1]heptan-2-ol [507-70-0]. Many other components of piae oils are also found, depending on the source of the turpentine used and the method of production. 

Terpin hydrate [2451-01-6] (10), one of the most weU-known expectorants, is isolated from cmde pine rosin left after the distillation of volatile terpene hydrocarbons and alcohols. It is also manufactured from turpentine (a-pinene) by acid-cataly2ed hydration. Terpin hydrate may exist as cis and trans isomers, but only the cis isomer forms a stable, crystalline monohydrate. Terpin hydrate is available in the United States only in prescription products. 

It is possible, however, that camphene hydrochloride is not a uniform body, but that some of the terpene suffers some rearrangement in the molecule by the action of hydrochloric acid, and that the hydrochloride consists of a mixture of a-camphene hydrochloride and /8-camphene hydrochloride there is, however, no evidence to suggest that camphene itwlf is a mixture of two terpenes, so that the two camphenes are not known to exist. Aschan obtained an alcohol, camphene hydrate, by acting on camphene hydrochloride with milk of lime, a reagent which does not produce molecular rearrangement in the terpene nucleus. 

A terpene yielding isofenchyl alcohol on hydration, which Wallach considers to be one of the fenchenes, was artificially prepared by converting nopinone into a hydroxy ester by means of bromoacetic ester and zinc-dust. The hydroxy ester is dehydrated by potassium bisulphate, and so yields an unsaturated ester, which on saponification yields an acid from which the terpene results by distillation. This fenchene has the following characters —... 

When the terpene a-fenchene (isopinene) is hydrated by means of acetic and sulphuric acids, it yields an isomer of fenchyl alcohol, which is known as isofenchyl alcohol (q.v.), and which on oxidation yields iso-fenchone, as fenchyl alcohol yields fenchone. The two ketones, fenchone and isofenchone, are sharply differentiated by isofenchone yielding iso-fenchocamphoric acid, Cj Hj O, on oxidation with potassium permanganate, which is not the case with fenchone. According to Aschan,i the hydrocarbon found in turpentine oil, and known as /9-pinolene (or cyclo-fenchene—as he now proposes to name it), when hydrated in the usual manner, yields both fenchyl and isofenchyl alcohols, which on oxidation yield the ketones fenchone and isofenchone. According to Aschan the relationships of these bodies are expressed by the following formulae —... 

The use of zeolites like ZSM-5 for hydration of cyclohexene has seen successful in industry. Van der Waal et al. (1996) have hydrated a-pinene to a-terpeniol with p-zeolite bycyclic terpenes are obtained as by-products. 

DIPA See diisopropanolamine. dip-o or de T pe a dipentene org chem A racemate of limonene. dT pen,ten dipentene glycol See terpin hydrate. dT pen.ten glT,k6l dipentene hydrochloride See terpene hydrochloride. dT pen,ten,hT-dr3 kl6r,Td ) diphacinone orgchem C23H16O3 A yellow powder with a melting point of 145-147°C used to control rats, mice, and other rodents acts as an anticoagulant. do fas-3,non ... 

Terpineols are unsaturated monocyclic terpene alcohols and are formed by acid-catalyzed hydration of pinenes a-, (3-, 7- and 6-isomers exist ... 

Hydrogenation of a-terpineol yields />-menthan-8-ol. Terpineol is readily dehydrated by acids, yielding a mixture of unsaturated cyclic terpene hydrocarbons. Under mildly acidic conditions, terpin hydrate is formed. The most important... 

Balsam turpentine oil is obtained from the resins of living trees of suitable Pinus species by distillation at atmospheric pressure and temperatures up to 180°C, or by other fractionation methods, which do not change the terpene composition of the resins. Wood turpentine oils, on the other hand, are generally obtained by steam distillation of chopped tree trunks, dead wood, or of resin extracted from this wood. Sulfate turpentine oil is produced as waste in the manufacture of cellulose by the sulfate process and is also a wood turpentine. Pine oil is another wood turpentine oil that is obtained by dry distillation of suitable pine and fir trees, followed by fractionation. However, the term pine oil is nowadays used for a product which is manufactured by hydration of turpentine oil (a-pinene). The resulting product is a mixture of monoterpenes containing o-terpineol as the main component. In addition to many other technical purposes, it is used to a large extent in cheap perfumes for technical applications. 

IPP and DMAPP lead to geranylpyrophosphate (GPP), which is an immediate precursor of monoterpenes. The formation of nerylpyrophosphate (NPP) from GPP gives rise to a wide range of acyclic, cyclic, bicyclic or tricyclic skeletons. Reactions like rearrangement, oxidation, reduction and hydration via various terpene cyclases result in the formation of numerous terpene derivatives. Condensation of GPP and IPP leads to farnesylpyrophosphate (FPP), the immediate precursor of sesquiterpenoids. Likewise, FPP and IPP are conducive to diterpenoids. 

Cornwell, P.A., et al. 1994. Wide-angle x-ray diffraction of human stratum corneum Effects of hydration and terpene enhancer treatment. J Pharm Pharmacol 46 938. 

The abovementioned materials can be mixed with one another. A series of other polymers and resins can also be added if the substances listed in 1 to 4 form the bulk of the material. Additional materials are PE, PP, low molecular weight polyolefins, polyterpenes (mixtures of aliphatic and cycloaliphatic hydrocarbons produced by polymerisation of terpene hydrocarbons), polyisobutylene, butyl rubber, dammar gum, glycerine and pentaerythritol esters of rosin acid and their hydration products, polyolefin resins, hydrated polycyclopentadiene resin (substance mixtures manufactured by thermal polymerization of a mixture mainly composed of di-cyclopentadiene with methylcyclopentadiene, isoprene and piperylene which is then hydrogenated). 

Turpentine. Turpentine is used directly as a solvent, thinner, or additive for paints, varnishes, enamels, waxes, polishes, disinfectants, soaps, pharmaceuticals, wood stains, sealing wax, inks, and crayons, and as a general solvent. The chemistry of its mono-terpenes offers many possibilities for conversion to other substances, as illustrated in Fig. 28.20. There is increasing use of turpentine to produce fine chemicals for flavors and fragrances. An important use of turpentine is in conversion by mineral acids to synthetic pine oil. It also is a raw material for making terpin hydrate, resins, camphene, insecticides, and other useful commodities. These uses are included in the following summary of its applications. 

The hydration/isomerization of alpha-pinene catalyzed by zeolite H-BEA is fast and leads mainly to monocyclic terpenes and alcohols with alpha-terpineol 32 as the principal product (up to 48%) (35). The selectivity to bicyclic products is about 26% which, while still too low, is significantly better than the 5% observed for H2SO4. 

Catalytic transformations of terpenes are well documented [213-215], comprising a wide variety of reactions hydrogenation, dehydrogenation, oxidation, hy-droformylation, carbonylation, hydration, isomerization and rearrangement, and cyclization. 

Figure 5.6 Proposed mechanism for the cyclization of geranyl diphosphate to sabinene and sabinene hydrate under catalysis by monoterpene synthases the reaction begins with the hydrolysis of the diphosphate moiety to generate a resonance-stabilized carbocation (1) the carbocation then isomerizes to an intermediate capable of cyclization by return of the diphosphate (2) and rotation around a single bond (3) after a second diphosphate hydrolysis (4) the resulting carbocation undergoes a cyclization (5) a hydride shift (6) and a second cyclization (7) before the reaction terminates by deprotonation (8) or capture of the cation by water (9). Cyclizations, hydride shifts and a variety of other rearrangements of carbocationic intermediates are a characteristic of the mechanisms of terpene synthases. No known terpene synthase actually produces both sabinene and sabinene hydrate these are shown to indicate the possibilities for reaction termination. PP indicates a diphosphate moiety.

Terpin. Terpin Hydrate. Cineol.—In addition to these monohydroxy derivatives there is another important one which is a dihydroxy menthane known as terpan-di-ol or terpin. Terpin boils at 258° and readily forms a crystalline hydrate, terpin hydrate, which melts at 117°. It also loses water yielding an anhydride known as cineol. Terpin and terpin hydrate are obtained from the terpenes in oil of turpentine by the action of acids. Cineol is found in eucalyptus oil. The constitution of these compounds is proven by their relation to geraniol (p. 167). When treated with 5 per cent H2SO4 two molecules of water are added to geraniol and terpin hydrate is formed. This by loss of one molecule of water forms a closed ring yielding terpin and this by loss of another molecule of water yields cineol. These relationships are as follows ... 

Use Solvent for protective coatings, polishes, and waxes synthesis of camphene, camphor, geraniol, terpin hydrate, terpineol, synthetic pine oil, terpene esters and ethers, lubricating oil additives, flavoring odorant. 

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