Alcohol monoterpenoid

Mono-COT compounds, 25 441 Monocots, fibers from, 27 18 Monocotyledonous grains, 26 267 Monocryl sutures, 24 222 Monocyclic monoterpenoid alcohols,... 

Monosodium L-glutamate (MSG), 12 49 Monosodium phosphate (MSP), 18 833 manufacture of, 18 853, 857-858 thermal dehydration of, 18 846 Monostatic optical arrangement, 23 139 Monosubstituted boranes, 13 635-636 Monoterpenoid alcohols, 24 500-528 bicyclic, 24 527-528 monocyclic, 24 509-527 Monoterpenoid aldehydes, 24 529-536 Monoterpenoid ethers, 24 528-529 Monoterpenoid hydrocarbons,... 

G.l.c. papers of interest include the classification of 22 acyclic monoterpenoid alcohols according to retention indexes, resolution of cyclic ketones [e.g. ( )-menthone, ( )-isomenthone] as diethyl (+)-tartrate acetals, and the use of lanthanide shift reagents to resolve non-terpenoid racemic epoxides.The occurrence and prevention of monoterpenoid hydrocarbon isomerization during silica gel chromatography has been examined and the separation of monoterpenoids and sesquiterpenoids by gel permeation chromatography is reported. Monoterpenoid hydrocarbons have been selectively extracted from essential oils using dimethylsilicone. ... 

Selective catalytic hydrogenation with chromium-promoted Raney nickel is reported (e.g. citral and citronellal to citronellol) NaHCr2(CO)io and KHFe(CO)4 reduction of a/3-unsaturated ketones (e.g. citral to citronellal) has been described (cf. Vol. 7, p. 7). The full paper on selective carbonyl reductions on alumina (Vol. 7, p. 7) has been published." Dehydrogenation of monoterpenoid alcohols over liquid-metal catalysts gives aldehydes and ketones in useful yields. ... 

Some early and obvious questions about bark beetle pheromone components concerned their origins are they synthesized de novo from acetate or derived from plant precursor molecules And are the biochemical reactions performed by insect tissues or symbiotic bacteria Ipsdienol and ipsenol are clearly monoterpenoid alcohols. Since de novo monoterpenoid biosynthesis was unprecedented in the Metazoa before 1995, and monoterpenes are produced by host trees, it seemed logical that monoterpenoid pheromone components were derived from ingested plant precursor molecules (reviewed in Vanderwel and... 

The reaction of linalool with boron trifluoride etherate has been re-examined no pinenes or camphene were obtained.146 Dehydrolinalool reacts with methyl iso-propenyl ether under acidic conditions by Claisen rearrangement to give the allene (58).147 Further papers in this section include reaction of monoterpenoid alcohols with paraformaldehyde-acetic anhydride-sodium acetate,148 rearrangement of the alcohol (47 X = OH) to the oxabicycloheptane (59) and the ketone (60),149 and the rearrangement of a typical monoterpenoid vicinal hydroxy-ester to an epoxide.150... 

Oxygenated monoterpenoids (alcohols, aldehydes, ketones and other oxygen-containing compounds) are flavour determining components of essential oils and more important from practical aspects than monoterpenic hydrocarbons. 

Mass spectral papers include another compilation of monoterpenoid alcohol spectra, a comparison of fragmentation patterns for camphor and menthone with their oxime, semicarbazone, and nitrophenylhydrazone derivatives, and a comparison of collisional activation mass spectra of ten related acyclic, monocyclic, and bicyclic monoterpenoid hydrocarbons together with derived 7119 ions. ... 

A cell-free extract from T. vulgare has been prepared that synthesized geraniol and nerol from [2- C]MVA and [4- " C]IPP in high yield (2.4% and 11.9% respectively). Dimethylvinylcarbinol was also incorporated efficiently into monoterpenoid alcohols by the system and this raises the important issue as to its role in monoterpenoid biosynthesis. Both dimethylvinylcarbinol pyrophosphate and DMAPP inhibited the formation of monoterpenoids from (3/ )-[2- C]MVA by the cell-free preparation, and the marked change in the proportions of geraniol and nerol produced in the presence of these additives led to the conclusion that two prenyltransferases were present in the system. The cell-free extract also incorporated [9,10- C2]-a-terpineol and [7- C]terpinen-4-ol into isothujone. The cyclase activity appeared to be associated with a particulate fraction. 

A further collection of mass spectra of hydrocarbons of the carane and menthane series has been published. The identification of monoterpenoid alcohols in complex mixtures is sometimes tedious it has been suggested that the problem would be simplified by preparing the trifluoroacetates, and using the n.m.r. spectra. ... 

Terpineol, or more strictly, a-terpineol (3.38), is one of the most widespread of monocyclic monoterpenoid alcohols in nature. It is found in flowers such as narcissus and freesia herbs such as sage, marjoram, oregano and rosemary in the leaf oil of Ti-tree Melaleuca alternifolia) and in the oil expressed from the peel of lemons. Reports of the level of terpineol in oils occasionally vary considerably and one wonders how much this is due to variations in the plants and to variations in the isolation process since terpineol could be an artefact. The layman will often describe the odour of terpineol as pine disinfectant since terpineol is, in fact a major component of pine disinfectant. This product is prepared by distillation of turpentine in the presence of acid which results in opening of the ring of a-pinene (3.37) to produce a-terpineol as shown in Figure 3.19. 

Figure 10.8 shows three monoterpenoid alcohols geraniol (10.16), citronellol (10.21) and linalool (10.22) all of which have been mentioned earlier as being key fragrance ingredients which can be obtained from natural sources. Geraniol is one of the character impact components of rose but it is only present in rose oils to the extent of about 30%. Much... 

Phenyl trifluoromethyl ketone has been used as a standard for comparing stereoselectivities in Meerwein-Ponndorf-type reductions with chiral alkoxyalu-minium and magnesium halides derived from monoterpenoid alcohols, and (24) is one of the few to show high selectivity (77% enantiomer excess). The alkylative addition of butyl-lithium to aldehydes in chiral media has been studied as part of a general programme to develop auxiliaries, based on tartaric acid, for asymmetric synthesis. Optical yields of up to 40% in the butyl carbinol products are obtained at low temperature in solutions containing chiral 1,2-dihetero-ethane derivatives such as (25), which are believed to complex the alkyl-lithium as in (26). 

In addition, acyl esters of terpenoid alcohols have been reported. For example, Dunphy and Allcock (1971) showed that 30-60% of the total monoterpenoid alcohol content of rose petals occurred as acyl esters with geranyl stearate predominating. 

Figure 6.18 shows a selection of cyclic monoterpenoid alcohols. a-Terpineol (74) is found in many essential oils as is its acetate. The isomeric terpinen-4-ol (93) is an important component of Ti tree... 

Centris adani are dominated by a variety of monoterpenoid alcohols, acids, and acetates (Vinson et al., 1982). Other species of Centris show no detectable mandibular gland secretions. 

Monocyclic Monoterpenoid Alcohols and Their Esters a-Terpineol... 

The seeds contain glucides (coniferin, syrin-gin, benzyl-P-D-glucopyranoside and others), monoterpenoid alcohols, 2-8% (usually 3-7%) volatile oil, about 15% lipids, 20% protein, a (3(1 4) mannan, and flavonoids (quercetin-3-glucuronide, isoquercitrin, etc.), furano- and hydroxycoumarins, among others (jiANGSu marsh wichtl). "... 

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