13371-12-5

Upstream product

• 2216-51-5 (-)-menthol 
• 72020-06-5 2-((1R,2S,5R)-2-isopropyl-5-methylcyclohexyloxy)tetrahydro-2H-pyran 
• 77774-21-1 l-(-)-(Menthyloxy)triphenylphosphonium triflate 
• 15356-60-2 (1S,2R,5S)-(+)-menthol 
• 70894-19-8 2-(((1R,2S,5R)-2-isopropyl-5-methylcyclohexyl)oxy)-2-oxoacetic acid 
• 117800-93-8 l-menthyl 8-quinolinesulfonate 
• 1082742-74-2 C₂₂H₃₄O₇S 
• 87161-57-7 (1S,2S,4R)-2-bromo-1-isopropyl-4-methylcyclohexane 

Downstream Products

• 43077-31-2 {1R-(1α,2β,5α)}-diphenylmenthylphosphine 
• 35836-63-6 (1r,4r)-1-(2-chloropropan-2-yl)-4-methylcyclohexane 
• 829-85-6 diphenylphosphane 
• 137724-75-5 1-Menthyl cation 
• 1357000-40-8 2-((1R,2R,5R)-2-isopropyl-5-methylcyclohexyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane 
• 898543-45-8 (1S,2R,4R)-2-azido-1-isopropyl-4-methylcyclohexane 
• 1067638-22-5 (1R,2S,5R)-(-)-menthyl methyl selenide 

Relevant academic research and scientific papers

(-)-Menthol as a source of new N,N-diamine ligands for asymmetric transfer hydrogenation

The synthesis of new chiral N-monotosylated-1,2-diamines based on the (-)-menthol skeleton is presented. The elimination of HCl from neomenthyl chloride obtained from an Appel reaction led to p-menth-3-ene in excellent yield. Further functionalization of the double bond in p-menth-3-ene with chloramine-T gave the corresponding N-tosylaziridines, which upon reaction with sodium azide and subsequent reduction of the azide functional group, formed the 1,2-diamine system. The synthesized chiral ligands proved effective in the asymmetric transfer hydrogenation of aromatic ketones and an endocyclic imine.

Radical Deoxychlorination of Cesium Oxalates for the Synthesis of Alkyl Chlorides

A radical deoxychlorination of cesium oxalates has been developed for the preparation of hindered secondary and tertiary alkyl chlorides. The reaction tolerates a number of functional groups, including ketones, alcohols, and amides, and provides complementary reactivity to standard deoxychlorination reactions proceeding by heterolytic mechanisms. Preliminary studies demonstrate that the developed conditions can also be applied to deoxybromination and deoxyfluorination reactions.

A mild method for the replacement of a hydroxyl group by halogen: 2. unified procedure and stereochemical studies

N,N-Dimethyl- and N,N-diisopropyl-1-halo-2-methyl-l-propenylamines are readily available reagents for the mild deoxyhalogenation of alcohols and hydroxyacids. In this study we showed that the reactivity of the reagents can be tuned by varying the size of the alkyl groups on the reagents: the replacement of methyl by isopropyl groups led to a significant increase of reactivity. We then described a unified procedure for all deoxyhalogenations using the readily available α-chloroenamines as reagents with (bromination, iodination) or without (chlorination) an alkaline bromide or iodide. Finally, we showed that deoxyhalogenation reactions of secondary alcohols were highly stereospecific and generally occurred with inversion of configuration.

Rearrangement in Stereoretentive Syntheses of Menthyl Chloride from Menthol: Insight into Competing Reaction Pathways through Component Quantification Analysis

The enantiopure reagent menthyl chloride (2) is generally prepared from (–)-(1R)-menthol (1) with Lucas' reagent (ZnCl2 in conc. aqueous HCl) in a stereoretentive reaction that appeared to be free from accompanying rearrangements. The same was assumed for a recent synthesis of 2 through TiCl4-catalyzed extrusion of SO2 from menthyl chlorosulfite (3). The products of both syntheses have now been analyzed by quantitative 1H and 13C NMR methods, and all reaction components have been identified down to the ≤ 0.5 mol-% level. Either reaction is accompanied by cationic rearrangement to the considerable extent of 18–25 mol-%. Besides the expected 2, neomenthylchloride (4) and five rearrangement products have been identified, among them three regioisomeric tertiary chloromenthanes (9, 10, 11), and both a secondary (12) and tertiary chloride (16) derived from ψ-menthane (1-isobutyl-3-methylcyclopentane). A scheme of rearrangement pathways starting from a common menthyl carbenium ion pair is derived. The effect of purification protocols on crude 2 has been studied quantitatively. Either selective solvolysis of tertiary sideproducts (98 mol-% purity) or low-temperature crystallization (≥ 97 mol-% purity) was successful. An improved, scalable synthesis of 2 through the catalytic rearrangement of chlorosulfite 3 is reported.

Sulfonyl halide synthesis by thiol oxyhalogenation using NBS/NCS – iPrOH

A rapid and facile method provides a general route to sulfonyl bromides/chlorides by the oxidation of thiols using NXS – ROH (X?=?Br,Cl, R?=?iPr) as an oxyhalogenation reagent. Control experiments suggest that the alcohol component is the source of oxygen. The proposed method enable the access to structurally diverse sulfonyl bromides and chlorides including challenging examples, inaccessible by other synthetic methods.

Manganese-Catalyzed Borylation of Unactivated Alkyl Chlorides

The use of low-cost manganese(II) bromide (MnBr2) and tetramethylethylenediamine (TMEDA) catalyzes the cross coupling of (bis)pinacolatodiboron with a wide range of alkyl halides, demonstrating the first manganese-catalyzed coupling with alkyl electrophiles. This method allows access to primary, secondary, and tertiary boronic esters from the parent chlorides, which were previously inaccessible as coupling partners. The reaction proceeds in high yield with as little as 1000 ppm catalyst loading, while 5 mol % can provide high yields in as little as 30 min. Finally, radical-clock experiments revealed that at 0 °C direct borylation outcompetes alternative radical processes, thereby providing synthetically useful, temperature-controlled reaction outcomes.

Iodobenzene Dichloride in the Esterification and Amidation of Carboxylic Acids: In-Situ Synthesis of Ph3PCl2

A novel, in-situ synthesis of dichlorotriphenylphosphorane (Ph3PCl2) is accomplished upon combining PPh3and the easily prepared hypervalent iodine reagent iodobenzene dichloride (PhICl2). The phosphorane is selectively generated in the presence of carboxylic acid or alcohol residues to rapidly produce acyl chlorides and alkyl chlorides in high yields. Addition of EtOH, PhOH, BnOH, Et2NH or CH2N2results in the direct synthesis of esters, amides and diazo ketones from carboxylic acids.

Terpenyl selenides: Synthesis and application in asymmetric epoxidation

Abstract Synthesis of terpenyl selenides derived from limonene, menthol, caranol, and myrtanol is described. Three methodologies for the synthesis of terpenyl selenonium salts are compared. The results of selenium-mediated epoxidation through the use of isoselenocineole derived from limonene and methyl terpenyl, phenyl terpenyl, diterpenyl selenides, and selenonium salts are presented. The influence of solvent, counteranion, and diastereomeric purity of selenonium salt on the enantioselectivity of the epoxidation reaction is discussed. Selenium-mediated asymmetric epoxidation through the use isoselenocineole, and methyl terpenyl, phenyl terpenyl, and diterpenyl selenides is presented. The influence of reaction conditions, counteranion, and purity of selenonium salt on the reaction of asymmetric epoxidation is described.

Synthesis and structures of (-) menthyl and (+) neomenthyl substituted enantio pure bis(1,2,3-triazol-5-ylidene)PdI2 complexes and PEPPSI type (1,2,3-triazol-5-ylidene) (pyridine)PdI2complexes. Comparison of catalytic activities for C-C coupling

(-) Menthol was converted to 1-menthyl-3-methyl-4-phenyltriazolium iodide and 1-neomethyl-3-methyl-4-phenyltriazolium iodide in four steps. These triazolium salts that are enantio pure but diastereo isomers, served as precursors for the synthesis of the corresponding enantio pure bis(1,2,3-triazol-5-ylidene)PdI2 complexes with menthyl and neomenthyl wing tip groups. The palladium complexes were synthesized in high yields using a recently developed mild method under base free and silver free conditions at ambient temperature. These triazolium salts also served as precursors for the synthesis of the corresponding enantio pure PEPPSI type (1,2,3-triazol-5-ylidene) (pyridine)PdI2 complexes. All the complexes were thoroughly characterized by spectroscopic and single crystal XRD data. The relative catalytic activities of these complexes were compared for Suzuki-Miyaura C-C coupling.

Synthesis and reactions of the optically active selenols derived from monoterpenes Dedicated to Professor Jacek Gawronski on the occasion of his 70th birthday

A convenient methodology for the synthesis of optically active selenols, derived from p-menthane, carane, and pinane, is described. The selenols were oxidized with air to give the optically active diselenides, and were also converted into the corresponding allylic selenides via reaction with Z- and E-cinnamyl, geranyl, and neryl chlorides. Oxidation of the allylic selenides with mCPBA gave the optically active alcohols via [2,3]-sigmatropic rearrangement of the in situ generated allylic selenoxides.