Fenchole

Fenchol (1,3,3-trimethyl-2-nor-bornanole) are bicyclic monoterpene - alcohols with molecular formula C ₁₀ H ₁₈ O and the molar mass of 154.25  g · mol ^-1 . There are four stereoisomers of the natural product isomeric with borneol , namely the α-fenchols [(+) - and (-) - α-fenchol] and the β-fenchols [(+) - and (-) - β-fenchol] which the hydroxyl group is above the levels of the six-membered ring. You come z. As in rosemary , hops , nutmeg oil and pine oil , and fruits such as lime , the grapefruit and peel of orange in front.

properties

Natural fenchol extracted from plants is always a mixture of the four different isomers (CAS number: 1632-73-1) with an overall camphor- like odor, the composition of which depends on the plant species. There is therefore no defined melting point (range from 35 to 40 ° C) or boiling point (~ 200 ° C) for the mixture. The individual isomers each have their own odor, ranging from lime-like to camphor-like to wood-like, earthy . The taste is bitter and lime-like . The fenchols are almost insoluble in water, but easily soluble in ethanol . The (+) - α-isomer has an irritant effect on eyes, skin and mucous membranes.

Isomers

Fenchole
Short name	(+) - α-fenchol	(-) - α-fenchol	(±) -α-fenchol	(±) -α / β-fenchol	(+) - β-fenchol	(-) - β-fenchol	(±) -β-fenchol
IUPAC name	(+) - (1 R , 2 R , 4 S ) -α-fenchol	(-) - (1 S , 2 S , 4 R ) -α-fenchol			(+) - (1 S , 2 R , 4 R ) -β-fenchol	(-) - (1 R , 2 S , 4 S ) -β-fenchol
Structural formula			1: 1 mixture of (+) - α-fenchol and (-) - α-fenchol	Not further defined mixture of four stereoisomers			1: 1 mixture of (+) - β-fenchol and (-) - β-fenchol
CAS number	2217-02-9	512-13-0	36386-49-9	1632-73-1	64439-31-2	470-08-6	36386-50-2
Physical state	firmly					liquid
Brief description	colorless solid					colorless oil
Melting point	47-47.5 ° C	43.7-48.5 ° C	38 ° C	35-40 ° C	26-27 ° C	7-8 ° C	6 ° C
boiling point		94 ° C (20 mmHg)	200 ° C	~ 200 ° C			201 ° C
solubility	insoluble in water, soluble in ethanol
odor		woody, earthy camphor-like		characteristic lime-like
GHS labeling	no classification available	no classification available	Caution	no GHS pictograms	no classification available	no classification available	no classification available
H and P phrases	see above	see above	315-319-335	no H-phrases	see above	see above	see above
	see above	see above	no EUH phrases	no EUH phrases	see above	see above	see above
	see above	see above	261-305 + 351 + 338	no P-phrases	see above	see above	see above

Presentation, reactions and use

Fenchols can be prepared by reducing fenchone with sodium in ethanol . The unsaturated fenchene , which are rarely found in essential oils , are formed by dehydrating fenchols .

(-) - α-Fenchol is used as a component in perfumes . Also in bergamot oil contained small amounts fenchol.

Natural fenchol is classified as FEMA GRAS ( G enerally R eported A s S afe , FEMA GRAS # 2480) in the United States and can therefore be used as a food additive . In 2003, 316.67 pounds (= 143.6 kg) of fenchols were used as odorous substances in the USA  ; the permitted daily dose was set at 0.533 mg.

Individual evidence

1. ↑ ^{a b} entry on fenchol. In: Römpp Online . Georg Thieme Verlag, accessed on June 13, 2014.
2. ↑ Michèle Lees: Food authenticity and traceability. Woodhead Publishing, 2003, ISBN 978-1-85573-526-2 , p. 208.
3. ↑ ^{a b} George A. Burdock: Encyclopedia of Food and Color Additives. CRC Press, 1996, ISBN 978-0-8493-9416-4 , p. 1091.
4. ↑ TheGoodsCompany: fenchol
5. ↑ ^{a b c d e} Fenchole data sheet (PDF) from Carl Roth , accessed on December 14, 2010.
6. ↑ JIG Codagan, J. Buckingham, FJ MacDonald, PH Rhodes: Dictionary of organic compounds. 6th edition, pp. 6288, CRC Press, 1996, ISBN 978-0-412-54090-5 .
7. ↑ ^{a b c d e f g h i j} S. Yanna: Dictionary of Food Compounds with CD-ROM: Additives, Flavors, and Ingredients. CRC Press, 2003, ISBN 978-1-58488-416-3 , pp. 1394-1395
8. ↑ ^{a b} TheGoodsCompany: Data for (-) - alpha-fenchol
9. ↑ Claudia Synowietz (Ed.): Paperback for chemists and physicists . founded by Jean d'Ans, Ellen Lax. 4th edition. Volume II: Organic Compounds . Springer, Berlin 1983, ISBN 3-540-12263-X .
10. ↑ Fenchyl alcohol data sheet from Sigma-Aldrich , accessed on April 29, 2011 ( PDF ).
11. ^ University of Erlangen : Natural Products Chemistry: Terpenes ( Memento from December 3, 2008 in the Internet Archive ), lecture script.
12. ^ Dictionary of Flavors. 2nd edition, Wiley-Blackwell, 2009, ISBN 978-0-8138-2135-1 , p. 78.
13. ^ GA Burdock, G. Fenaroli: Fenaroli's handbook of flavor ingredients. 5th edition, CRC Press, 2004, ISBN 978-0-8493-3034-6 , p. 654.