490-99-3

Basic information

• Product Name: isomenthol
• CAS NO: 490-99-3
• Molecular Formula: C₁₀H₂₀O
• Molecular Weight: 156.2652
• Mol File: 490-99-3.mol

Chemical Properties

• CAS DataBase Reference: isomenthol(CAS DataBase Reference)
• NIST Chemistry Reference: isomenthol(490-99-3)
• EPA Substance Registry System: isomenthol(490-99-3)

Safety Data

• Hazardous Substances Data: 490-99-3(Hazardous Substances Data)

Upstream product

• 89-83-8 thymol 
• 491-07-6 (+/-)-menthone 
• 555-31-7 aluminum isopropoxide 
• 89-81-6 piperitone 
• 14539-76-5 rac-neomenthyl-4-tolylsulfonate 
• 10458-14-7 Menthone 
• 60-29-7 diethyl ether 
• 64-17-5 ethanol 
• 67-56-1 methanol 
• 29801-64-7 (+/-)-1-methyl-4r-isopropyl-cyclohexen-⁽¹⁾-ol-(5c) 
• 491-04-3 (1R*,6S*)-6-isopropyl-3-methylcyclohex-2-en-1-ol 
• 5392-40-5 (E/Z)-3,7-dimethyl-2,6-octadienal 
• 106-23-0 3,7-dimethyl-oct-6-enal 
• 15356-60-2 (1S,2R,5S)-(+)-menthol 

Downstream Products

• 89-48-5 menthyl acetate 
• 10458-14-7 (2R,5S)-menthone 
• 64-19-7 acetic acid 
• 26127-08-2 (1R,2S,5R)-1-(chloromethoxy)-2-isopropyl-5-methylcyclohexane 
• 914769-32-7 (1S,4R)-2-iodo-4-methyl-1-(1-methylethyl)cyclohexane 

Relevant articles and documents

Continuous synthesis of menthol from citronellal and citral over Ni-beta-zeolite-sepiolite composite catalyst

One-pot continuous synthesis of menthols both from citronellal and citral was investigated over 5 wt% Ni supported on H-Beta-38-sepiolite composite catalyst at 60–70 °C under 10–29 bar hydrogen pressure. A relatively high menthols yield of 53% and 49% and stereoselectivity to menthol of 71–76% and 72–74% were obtained from citronellal and citral respectively at the contact time 4.2 min, 70 °C and 20 bar. Citral conversion noticeably decreased with time-on-stream under 10 and 15 bar of hydrogen pressure accompanied by accumulation of citronellal, the primary hydrogenation product of citral, practically not affecting selectivity to menthol. A substantial amount of defuctionalization products observed during citral conversion, especially at the beginning of the reaction (ca. 1 h), indicated that all intermediates could contribute to formation of menthanes. Ni/H-Beta-38-sepiolite composite material prepared by extrusion was characterized by TEM, SEM, XPS, XRD, ICP-OES, N2 physisorption and FTIR techniques to perceive the interrelation between the physico-chemical and catalytic properties.

Continuous flow synthesis of menthol: Via tandem cyclisation-hydrogenation of citronellal catalysed by scrap catalytic converters

A continuous flow synthesis of menthol starting from citronellal catalysed by scrap catalytic converters is reported. The reaction was conducted in a tandem system connecting in series two catalytic systems, with the first having Lewis acid properties (favouring the cyclisation of citronellal to isopulegols) and the second having hydrogenation catalytic activity (catalysing the hydrogenation of isopulegols to menthols). A Lewis acid catalyst was prepared by supporting iron oxide nanoparticles over a waste material, i.e. the ceramic core of scrap catalytic converters (SCATs) via a microwave assisted method. Most importantly, SCATs, containing a low residual noble metal content, could be directly employed in the second step as hydrogenation catalysts. The reaction was performed studying the influence on the yield and selectivity to (-)-menthol of various reaction parameters (T, p and flow rate). Under the best reaction conditions (at a flow rate of 0.1 mL min-1 and at 373 K and 413 K for cyclisation and hydrogenation steps respectively) a conversion of >99% of (+)-citronellal to (-)-menthol with 77% final yield was achieved.

A synthetic process of L-menthol

The invention relates to the field of spice synthesis and particularly relates to a synthetic process of L-menthol. The process includes steps of d,l-menthol synthesizing, d,l-menthol rectification, d,l-menthol esterification, d,l-menthyl benzoate rectification, d,l-menthyl benzoate resolution, D-menthol synthesizing, menthol isomerization and L-menthol synthesizing. The process adopts thymol that is a simple, easily available and cheap chemical product as a raw material. Esterification conditions are optimized and the esterification and rectification are performed at the same time so as to allow the esterification to be converted into a way beneficial to d,l-menthyl benzoate production, thus increasing the esterification yield. Crystallization and resolution are optimized by utilization of the d,l-menthyl benzoate. Preparation of the L-menthol by the process is characterized by being high in yield, low in cost, simple and convenient in operation, suitable for continuous and large-scale production, and the like. According to the process, operation of the process is cyclic with a whole system being sealed, and the process is free of waste water, energy-saving and environmental friendly.

P450-catalyzed regio- and stereoselective oxidative hydroxylation of disubstituted cyclohexanes: Creation of three centers of chirality in a single CH-activation event This paper is dedicated to the memory of Harry H. Wasserman

Wild-type P450-BM3 is able to catalyze in a highly regio- and diastereoselective manner the oxidative hydroxylation of non-activated disubstituted cyclohexane derivatives lacking any functional groups, including cis- and trans-1,2-dimethylcyclohexane, cis- and trans-1,4-dimethylcyclohexane, and trans-1,4-methylisopropylcyclohexane. In all cases except chiral trans-1,2-dimethylcyclohexane as substrate, the single hydroxylation event at a methylene group induces desymmetrization with simultaneous creation of three centers of chirality. Certain mutants increase selectivity, setting the stage for future directed evolution work.

Facile Protocol for Catalytic Frustrated Lewis Pair Hydrogenation and Reductive Deoxygenation of Ketones and Aldehydes

A series of ketones and aldehydes are reduced in toluene under H2 in the presence of 5 mol % B(C6F5)3 and either cyclodextrin or molecular sieves affording a facile metal-free protocol for reduction to alcohols. Similar treatment of aryl ketones resulted in metal-free deoxygenation yielding aromatic hydrocarbons.

PROCESS FOR THE PREPARATION OF MENTHOL

The invention relates to a process for the preparation of 2-isopropyl-5-methylcyclohexanol (menthol) via the hydrogenation of thymol to neomenthol and the subsequent isomerization to give D/L (+/?)-menthol.

PROCESS FOR THE PREPARATION OF MENTHOL

The invention relates to a process for the preparation of 2-isopropyl-5-methylcyclohexanol (D,L-menthol) via the hydrogenation of thymol to menthone and subsequent further hydrogenation to give D,L-menthol.

Highly practical iron-catalyzed C-O cleavage reactions

Facile iron-catalyzed cleavage of various allyl, cinnamyl and benzyl C-O linkages has been effected in the presence of ethylmagnesium chloride. The protocol is operationally simple (xylene-THF, r.t., 1 h), requires low catalyst loading (1 mol% FeCl2) and tolerates halides, esters, amines, ethers and olefins. The allyl moiety is converted to volatile hydrocarbons which renders laborious product separation unnecessary.

MOFs as multifunctional catalysts: One-pot synthesis of menthol from citronellal over a bifunctional MIL-101 catalyst

A bifunctional MOF catalyst containing coordinatively unsaturated Cr 3+ sites and palladium nanoparticles (Pd@MIL-101) has been used for the cyclization of citronellal to isopulegol and for the one-pot tandem isomerization/hydrogenation of citronellal to menthol. The MOF was found to be stable under the reaction conditions used, and the results obtained indicate that the performance of this bifunctional solid catalyst is comparable with other state-of-the-art materials for the tandem reaction: Full citronellal conversion was attained over Pd@MIL-101 in 18 h, with 86% selectivity to menthols and a diastereoselectivity of 81% to the desired (-)-menthol, while up to 30 h were necessary for attaining similar values over Ir/H-beta under analogous reaction conditions. The Royal Society of Chemistry 2012.

One-step microwave-assisted asymmetric cyclisation/hydrogenation of citronellal to menthols using supported nanoparticles on mesoporous materials

The selective conversion of citronellal to menthols, with good diastereoselectivities to (-)-menthol for the case of (+)-citronellal as starting material, can effectively be carried out in a one-step reaction under microwave irradiation catalysed by supported nanoparticles on mesoporous materials. 2% Pt/Ga-MCM-41 was found to be the optimum catalyst for the reaction, with a quantitative conversion of starting material and selectivities above 85% to menthols obtained in short reaction times (typically 15 min). These results constitute the first report of a simple microwave-assisted one-step cyclisation/hydrogenation process for the production of menthols.