7-Hydroxy-/?-menthane

Low-temperature fluorination of 9,9.9,10,10,10-hcxafluoro-y -mcnthanc-3,8-diol results in substitution of both hydroxy groups by fluorine to afford 3,8,9,9,9,10,10.10-octafluoro-/t-menthane (3).52... 

Spectral and Other Physical Data.—13C N.m.r. studies on hydroxy- and chloro-menthanes have revealed that certain shifts are very sensitive and reliable probes... 

Verghese has published a review about this class. Authentically naturally occurring m-menthanes are m-thymol (687, R = H) and its methyl ether 687 (R = Me), isolated from various Calea species as well as the isobutyl ether 687 (R = iBu) from Athrixia elata. Paknikar has synthesized 687 (R = H) by Grignard reaction of 2-hydroxy-5-methylacetophenone. ... 

Menthol is 3-hydroxy-p-menthane. It occurs widely in mint species and the richest source is commint Mentha arvensis, up to 85%). The three unsaturated analogues shown in Figure 4.9 occur in many mint oils. Pulegol also occurs in Eucalyptus citriodora and rose oils, isopulegol can account for up to 10% of the oil of E. citriodora and piperitol occurs... 

It should be observed that the word menthol has three separate meanings. Firstly, it is used generically to refer to all of the 3-hydroxy-p-menthanes. Secondly, it is used to mean specifically the thermodynamically most favourable pair of diastereomers in which all of the... 

Oxygenated p-Menthanes. The conformations of dihydrocarvone (148), the diastereoisomeric pairs of the corresponding 1-hydroxy-compound, and some related substances have been studied by temperature-dependent c.d. The conformations of the various stereoisomers (149) of the reduction products of carvotanacetone epoxide, as well as some of the corresponding alcohols from carvone epoxide (150) have been examined through their Hn.m.r. spectra. ... 

Epoxy-/7-menthane-2,4-diol, E-30089 lO-Hydroxy-8-decenoic acid, H-10109... 

Terpin n. Terpinol, 4-hydroxy-a,a,4-tri-methylcyclohexanemethanol. Additional names p-menthane-l,8-diol dipentenegly-col. Molecular formula C10H20O2. Molecular weight 172.26. Percent composition C 69.72%, H 11.70%, O 18.58%. Literature references from Merck Index, 13th edn. 2001 Both cis-and trans-modifications are known. The ds-compound is obtained most readily in the hydrated form, cis-terpin hydrate. Prepn of ds-form from oil of turpentine Hempel, Ann. 180, 71 (1876) Wallach, Ann. 230, 225 (1885) Schmitt, Mfg. Chemist 26, 350 (1955). From d-limonene Sword, /. Chem. Soc. 127y 1632 (1925). Prepn of trans-form from 1,8-cineole, oc-terpineol or ds-terpin hydrate. Matsuura et al. (1958) Bull Chem Soc Japan 31, 990. Lombard, Ambroise, Bull... 

Based on the aforementioned results, it is obvious that (+)-3p-hydroxy-l,8-cineole (123b) is formed mainly in the biotransformation of 1,8-cineole (122), (+)-3a-hydroxy-l,8-cineole (123b), and (+)-3-oxo-l,8-cineole (126a) by S. ikutamanensis Ya 2 1. The production of (+)-3p hydroxy-l,8-cineole (123b) is interesting, because it is a precursor of mosquito repellent, p-menthane-3,8-diol (142aa ) (Noma and Nishimura, 1981) (Figure 19.136). 

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