O-Terpineol

Terpineol of commerce is, in the main, a mixture of the isomers, in which o-terpineol largely predominates. 

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. 

The reaction of geraniol, nerol and linalool in the presence of VO(acac)2 -Me3SiOOSiMe3 in dichloromethane at 25 °C gave o -terpineol as the main product35. 

The naturally occurring molecule o -terpineol is biosynthesized by a route that includes the following step ... 

The pyrolysis of verbenene (685) leading to o-menthatrienes, has been reexamined, and a number of o-menthadienes and two stereoisomers of an o-terpineol (686) have been prepared from a Diels-Alder reaction between 1,3-pentadiene and methyl acrylate, with subsequent Grignard addition. ... 

Terpinenes, teipinols see p-menthadienes. Terpinenols, a-terpimol see p-menthenols. o-Terpineol acetate see oil of cardamom. Terprenin. 

Linalool o -Terpineol /8-Terpineol Propyl succinate Citronellol Menthol Capric acid Ethyl caprylate Isoamyl isovalerate n-Decyl alcohol Isoamyl sulfide Isobutyl benzoate Terpineol methyl ether Ethyl pelargonate Isoamyl carbonate 1,3,5-Triethylbenzene Bornyl acetate Bornyl ethyl ether Tridecane... 

The main products of limonene oxidation, carvone and carveol, cause a terpenic off-flavour in essential oils and juices. Valencene oxidation products, such as (-F)-nootkatone, cause a grapefruit-like off-flavour in orange juices. Large amounts of alcohol (-F)-o(-terpineol, which arises, for example, during storing of juices by acid catalysed hydration or microbial transformation of limonene, is also perceived as an off-flavour. 

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