4277-14-9

Upstream product

• 2216-51-5 (-)-menthol 
• 62-23-7 4-nitro-benzoic acid 
• 122-04-3 4-nitro-benzoyl chloride 
• 67392-57-8 (1R,2S,5R)-5-methyl-2-(1-methylethyl)cyclohexyl ester of diphenylphosphinous acid 
• 15356-70-4 menthol 
• 99-77-4 ethyl 4-nitrobenzoate 

Downstream Products

• 75350-80-0 8-fluoromenthyl p-nitrobenzoate 
• 75350-81-1 1,8-difluoromenthol p-nitrobenzoate 
• 75350-82-2 isopulegol 
• 5447-71-2 (1R,2S,5R)-2-isopropyl-5-methylcyclohexyl 4-aminobenzoate 
• 2216-51-5 (-)-menthol 

Relevant academic research and scientific papers

Copper-free Sandmeyer-type Reaction for the Synthesis of Sulfonyl Fluorides

A copper-free Sandmeyer-type fluorosulfonylation reaction is reported. Utilizing Na2S2O5 and Selectfluor as the sulfur dioxide and fluorine sources, respectively, aryldiazonium salts were transformed into sulfonyl fluorides. The one-pot direct synthesis of sulfonyl fluorides from aromatic amines was also realized via in situ diazotization. The practicality of this method was demonstrated by the broad functional group tolerance, gram-scale synthesis, and late-stage fluorosulfonylation of natural products and pharmaceuticals.

[Ph3C][B(C6F5)4]: A Highly Efficient Metal-Free Single-Component Initiator for the Helical-Sense-Selective Cationic Copolymerization of Chiral Aryl Isocyanides and Achiral Aryl Isocyanides

Commercially available [Ph3C][B(C6F5)4] served as a highly efficient metal-free and single-component initiator not only for the carbocationic polymerization of polar and bulky aryl isocyanides with extremely high activity up to 1.2×107 g of polymer/(molcat. h), but also for the helical-sense-selective polymerization of chiral aryl isocyanides and copolymerization with achiral aryl isocyanides to afford high-molecular-weight functional poly(aryl isocyanide)s with good solubility as well as AIE characteristics and/or a single-handed helical conformation.

Systematic Evaluation of 2-Arylazocarboxylates and 2-Arylazocarboxamides as Mitsunobu Reagents

2-Arylazocarboxylate and 2-arylazocarboxamide derivatives can serve as replacements of typical Mitsunobu reagents such as diethyl azodicarboxylate. A systematic investigation of the reactivity and physical properties of those azo compounds has revealed that they have an excellent ability as Mitsunobu reagents. These reagents show similar or superior reactivity as compared to the known azo reagents and are applicable to the broad scope of substrates. pKa and steric effects of substrates have been investigated, and the limitation of the Mitsunobu reaction can be overcome by choosing suitable reagents from the library of 2-arylazocarboxylate and 2-aryl azocarboxamide derivatives. Convenient recovery of azo reagents is available by one-pot iron-catalyzed aerobic oxidation, for example. SC-DSC analysis of representative 2-arylazocarboxylate and 2-arylazocarboxamide derivatives has shown high thermal stability, indicating that these azo reagents possess lower chemical hazard compared with typical azo reagents.

Advances and mechanistic insight on the catalytic Mitsunobu reaction using recyclable azo reagents

Ethyl 2-arylhydrazinecarboxylates can work as organocatalysts for Mitsunobu reactions because they provide ethyl 2-arylazocarboxylates through aerobic oxidation with a catalytic amount of iron phthalocyanine. First, ethyl 2-(3,4-dichlorophenyl)hydrazinecarboxylate has been identified as a potent catalyst, and the reactivity of the catalytic Mitsunobu reaction was improved through strict optimization of the reaction conditions. Investigation of the catalytic properties of ethyl 2-arylhydrazinecarboxylates and the corresponding azo forms led us to the discovery of a new catalyst, ethyl 2-(4-cyanophenyl)hydrazinecarboxylates, which expanded the scope of substrates. The mechanistic study of the Mitsunobu reaction with these new reagents strongly suggested the formation of betaine intermediates as in typical Mitsunobu reactions. The use of atmospheric oxygen as a sacrificial oxidative agent along with the iron catalyst is convenient and safe from the viewpoint of green chemistry. In addition, thermal analysis of the developed Mitsunobu reagents supports sufficient thermal stability compared with typical azo reagents such as diethyl azodicarboxylate (DEAD). The catalytic system realizes a substantial improvement of the Mitsunobu reaction and will be applicable to practical synthesis.

Synthesis, antimicrobial evaluation, and QSAR analysis of 2-isopropyl-5-methylcyclohexanol derivatives

A series of 2-isopropyl-5-methylcyclohexanol derivatives were synthesized and evaluated for their antibacterial activity against Gram-positive Staphylococcus aureus and Bacillus subtilis and Gram-negative Escherichia coli and in vitro antifungal activity against Candida albicans and Aspergillus niger. The results of antimicrobial activity demonstrated that the compounds 10, 20, and 21 were the most active ones among the synthesized compounds. The QSAR studies revealed the importance of dipole moment (μ), total energy (Te), and topological parameters (κ1 and κ3) in describing the antimicrobial activity of 2-isopropyl-5-methylcyclohexanol derivatives. Springer Science+Business Media, LLC 2011.

Easily prepared azopyridines as potent and recyclable reagents for facile esterification reactions. An efficient modified mitsunobu reaction

(Chemical Equation Presented) The 2,2′-, 3,3′-, and 4,4′-azopyridines (azpy) and their alkyl pyridinium ionic liquids were studied as a new class of electron-deficient reagents for Mitsunobu esterification reactions. Among these compounds, 4,4′-azopyridine was found to be the most suitable one for esterification and thioesterification reactions. This new reagent promises to provide general and complementary solutions for separation problems in Mitsunobu reactions without restricting the reaction scope and facilitates the isolation of its hydrazine byproduct. The pyridine hydrazine byproduct can be simply recycled to its azopyridine by an oxidation reaction.

Dimethylmalonyltrialkylphosphoranes: Probing the steric effect on phosphorus and its stereochemical consequence in esterification reactions of chiral secondary alcohols

High chemical yields and high levels of stereochemical inversion are demonstrated in the phosphorane-mediated esterification reaction of chiral alcohols with non-hindered carboxylic acids through the incorporation of sterically non-hindered alkyl groups o

Novel polymer-supported coupling/dehydrating reagents for use in organic synthesis

Two novel dehydrating reagents 3 and 4, based on a phosphonium anhydride and an oxyphosphonium triflate respectively, were prepared by reaction of the corresponding polymer-supported phosphine oxides with triflic anhydride. Reagent 3, based on the novel phosphorus heterocycle 1,1,3,3-tetraphenyl-2-oxa-1,3- diphospholanium bis(trifluoromethanesulfonate), was found to be a useful reagent for ester and amide formation. A wide range ofcoupling/dehydration-type reactions, such as ester, amide, anhydride, peptide, ether and nitrile formation, were performed in high yield using the more readily prepared polymer-supported triphenylphosphine ditrinate 4, which was easily recovered and re-used several times without loss of efficiency. With primary alcohols, both reagents 3 and 4 provide an alternative to the Mitsunobu reaction, where the use of azodicarboxylates and chromatography to remove the phosphine oxide by-product can be avoided. The use of 4-dimethylaminopyridine allowed the esterification of secondary alcohols with 4 to proceed in high yield but with retention of configuration.

Dimethylmalonyltrialkylphosphoranes: New general reagents for esterification reactions allowing controlled inversion or retention of configuration on chiral alcohols

A new class of trialkylphosphorane has been prepared through reaction of a trialkylphosphine with 2-chlorodimethylmalonate in the presence of triethylamine. These new reagents promote the condensation reaction of carboxylic acids with alcohols to provide esters along with trialkylphosphine oxide and dimethylmalonate. The condensation reaction of chiral secondary alcohols can be controlled to give either high levels of inversion or retention through a subtle interplay involving basicity of the reaction media, solvent, and tuning the electronic and steric nature of the carboxylic acid and steric nature of the phosphorane employed. A coherent mechanism is postulated to explain these observations involving reaction via an initial acyloxyphosphonium ion.

PHOSPHORANES AS COUPLING AGENTS AND THEIR PREPARATION

Provided is a use as a coupling agent for condensation reactions of a compound of formula (I): wherein each of R1, R2, and R3 is independently H, hydrocarbyl, or hydrocarbyloxy, provided that not more than one of R1, R2, and R3 is H ; and at least one of Y1 and Y2 is an electron-withdrawing group and the other, if not an electron-withdrawing group, is H or a group that has no electron-donating properties, with the proviso that when one of Y1 and Y2 is H, the other is not -CN. Some of the compounds of formula (I) are novel, and methods of their preparation are also provided.