31 results about "Methyl cyclohexane" patented technology

The invention discloses a system and a method for dehydrogenation of methyl cyclohexane by using a fuel cell. The system comprises an electrochemical dehydrogenation power generation unit which takes a solid oxide fuel cell as a reactor and is used for performing an electrochemical dehydrogenation reaction on methylcyclohexane to generate a dehydrogenation product containing toluene and simultaneously generating electric energy; the electrochemical hydrogenation unit takes a proton exchange membrane electrolytic tank as a reactor and is used for carrying out electrochemical hydrogenation reaction on toluene and hydrogen to generate methylcyclohexane; and in the material circulation loop, toluene generated by the electrochemical dehydrogenation power generation unit is at least partially conveyed to the electrochemical hydrogenation unit to serve as a reactant, and methylcyclohexane generated by the electrochemical hydrogenation unit is at least partially conveyed to the electrochemical dehydrogenation power generation unit to serve as a reactant. The electrochemical reaction path is used for replacing traditional thermocatalysis, the reaction efficiency is improved, the energy consumption is reduced, and the system is a green and efficient energy comprehensive utilization system.

A polyester-based polymer according to the present invention contains 30 mol% or more of cyclohexanedicarboxylic acid, dimethylcyclohexanedicarboxylate, or a combination thereof as a dicarboxylic acid component, and thus is environmentally friendly, has controlled softness, and has excellent quality and processability. In addition, the polyester-based polymer includes a linear C3-C6 alkanediol or the like as a diol component, thereby improving cold resistance, chemical resistance, and elasticity while having softness.

The application provides an improved naphthene hydrocarbon fuel and a low-pressure combustion promoting method thereof, in particular, methylcyclohexane is used as a base fuel, and diethylsilane is added to methylcyclohexane to regulate the ignition temperature and ignition delay time of methylcyclohexane at low pressure. The modified naphthene hydrocarbon fuel obtained by the method has the advantages of stable physical form, no stratification, high heat value, good stability when the fuel is in contact with air at normal temperature and the like, the low-pressure combustion characteristics of the naphthene hydrocarbon fuel are regulated through directional regulation of the combustion base element reaction of the naphthene hydrocarbon fuel, the operation is simple, and the practicability is strong. The application solves the problem of low-pressure regulation difficulty of the hydrocarbon fuel, provides a solution for the low-pressure characteristic regulation of the naphthene hydrocarbon fuel, and provides technical reserves for reliable ignition of advanced aero-engine under low-pressure harsh working conditions.

The invention relates to a plant-source attractant for peach tree pests and application of the plant-source attractant. The plant-source attractant is selected from any one or more of beta-phellandrene, 3-methylene-6-(tert-amyl) cyclohexane-1-ene, 1-isopropyl-4-methylene cyclohexane, 4-methylene cyclohexane-1-ethyl formate, 4-oxoisophorone and 3-carene, and the plant-source attractant is selected from any one or more of beta-phellandrene, 3-methylene-6-(tert-amyl) cyclohexane-1-ene, 1-isopropyl-4-methylene cyclohexane, 4-methylene cyclohexane-1-ethyl formate, 4-oxoisophorone and 3-carene. The compound can be used for preparing a preparation for attracting peach tree pests outdoors. Compared with the prior art, the peach tree pest plant source attractant can trap and kill female adults in external environments such as a field, and the prevention and control effect is greatly improved.

The invention belongs to the technical field of liquid organic hydrogen storage, and particularly relates to a molecular sieve catalyst for dehydrogenation of a liquid organic hydrogen storage carrier as well as a preparation method and application thereof. According to the preparation method of the molecular sieve catalyst for dehydrogenation of the liquid organic hydrogen storage carrier, a chelating agent and transition or rare earth metal are prepared into a doped metal solution, the doped metal solution and a molecular sieve precursor solution are subjected to a hydrothermal reaction, the transition or rare earth metal is doped into a molecular sieve through a hydrothermal method, and the molecular sieve catalyst is obtained. Loading platinum onto the molecular sieve through ion exchange; therefore, a rare earth / transition-platinum bifunctional efficient catalytic system is constructed, excellent catalytic performance is shown in a methyl cyclohexane dehydrogenation reaction, and a high-dispersion stable metal catalytic activity center of rare earth / transition metal and platinum is formed on a molecular sieve through a hydrothermal reaction and an ion exchange method. And the requirements of high activity and stability of the liquid organic hydrogen storage carrier dehydrogenation catalyst are met.

The invention relates to a preparation method of 1-fluoro-3-iodine-5-(trifluoromethyl) benzene. The 1-fluoro-3-iodine-5-(trifluoromethyl) benzene is used as a raw material. The preparation method of the 1-fluoro-3-iodine-5-(trifluoromethyl) benzene comprises the following steps: mixing 3-bromo-5-fluorobenzotrifluoride, iodized salt, a catalyst and an active agent, and then carrying out a reaction, so as to obtain the 1-fluoro-3-iodine-5-(trifluoromethyl) benzene, the active agent is trans-(1R, 2R)-N, N '-dimethyl-1, 2-cyclohexane diamine. The preparation method provided by the invention is simple and convenient to operate, the synthetic raw materials are economical and easy to obtain, and the 1-fluoro-3-iodine-5-(trifluoromethyl) benzene with excellent yield and purity can be efficiently obtained.

The utility model belongs to the technical field of naphtha separation, and relates to a device for producing methyl cyclohexane by using naphtha, which comprises a first heavy separation tower and a second heavy separation tower, a first light component is extracted at the tower top of the first heavy separation tower, and a first heavy component is extracted at the tower kettle of the first heavy separation tower; the second heavy separation tower is communicated with the tower top of the first heavy separation tower, a second light component is extracted from the tower top of the second heavy separation tower, a second heavy component is extracted from the tower kettle of the second heavy separation tower, and the second light component is methyl cyclohexane; according to the utility model, the first heavy separation tower and the second heavy separation tower are connected in series, a first light component extracted from the top of the first heavy separation tower enters the second heavy separation tower, and methyl cyclohexane is extracted from the top of the second heavy separation tower after the first light component is subjected to secondary fractionation in the second heavy separation tower by utilizing the boiling point difference of each component; high-purity extraction of the methylcyclohexane is realized, and the effective yield of the methylcyclohexane is improved, so that the economic benefit is improved.

The invention relates to a recycled, thermally stable polystyrene composition P, comprising a recycled polystyrene composition A, which comprises at least one polystyrene A-1 that is prepared by a thermally initiated and / or 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane initiated radical polymerization, and at least one sterically hindered phenolic antioxidant as component B. The invention also relates to a process for providing superior thermal stability in the mechanical recycling of polystyrene. Further, a recycled, thermally stable polystyrene composition P, a process for preparing the recycled, thermally stable polystyrene composition P and the use of the recycled, thermally stable polystyrene composition P for preparing molded articles are described.

The present invention relates to a polycarbonate composition comprising the following components, relative to the total weight of the composition: A) 0-76% by weight of a copolycarbonate resin containing bis (4-hydroxyphenyl)-3, 3, 5-trimethylcyclohexane units and substituted or unsubstituted bisphenol units, B) 0-58% by weight of an aromatic linear polycarbonate resin, C) 15-52% by weight of a poly (1, 3, 5-trimethylcyclohexane unit, D) 0-50% by weight of a polycarbonate resin, and E) 0-50% by weight of a polycarbonate resin. The present invention relates to a composition comprising: A) 1-60 wt% of 1, 4-cyclohexanedicarboxylic acid 1, 4-cyclohexylidene dimethylene ester), and D) 1-60 wt% of a methyl methacrylate-n-butyl acrylate-butadiene-styrene copolymer, the composition according to the present invention having high light transmittance, low haze and low birefringence.

The invention relates to the technical field of composite materials, in particular to a high-strength honeycomb paper core cover plate and a preparation process thereof. The preparation method comprises the following steps: taking isophorone diisocyanate, polycaprolactone diol, hydroxypropyl-terminated polysiloxane and acrylic acid-2-hydroxyethyl ester as raw materials, and reacting to obtain a mixed polyurethane prepolymer; the preparation method comprises the following steps: reacting 1, 3-bis (N, N-diglycidyl aminomethyl) cyclohexane with undecylenic acid to obtain a cross-linking agent; bisphenol A epoxy resin, the mixed polyurethane prepolymer, a cross-linking agent, a flame retardant, a photoinitiator, a plasticizer, a curing agent and deionized water are mixed and stirred to obtain epoxy modified polyurethane glue; the high-strength honeycomb paper core cover plate is obtained by using a glass fiber felt to wrap a honeycomb paperboard, spraying epoxy modified polyurethane glue on two sides, compounding with a fabric after photocuring, and heating and pressing. The prepared honeycomb paper core cover plate is high in strength, good in moisture resistance and not prone to cracking.

The present application relates to a dehydrogenation catalyst, its preparation method and application, and a methylcyclohexane dehydrogenation method, the catalyst comprising: Pt element, hydrocarbon complex and carrier; the hydrocarbon complex has a graphitization degree I D / I G = 1.9-1.2, wherein I D is the intensity of disordered carbon peak, and I G is the intensity of ordered carbon peak. It is proposed to introduce an organic compound in the reduction stage of catalyst preparation, and a dehydrogenation catalyst containing hydrocarbon complex is obtained. The organic compound is converted into hydrocarbon complex in situ during the reduction process of the catalyst, the high active sites in the catalyst are reasonably covered, the C-C bond activation ability of the active sites is weakened or eliminated, the C-H bond activation ability of the active sites is retained, and the dehydrogenation selectivity of the catalyst is improved without weakening the dehydrogenation activity of the catalyst.

The invention belongs to the technical field of catalysis, and particularly relates to an aluminum oxide catalyst loaded with platinum nanoparticles, a preparation method and application of the aluminum oxide catalyst, and a dehydrogenation method of a cycloalkane compound, the catalyst comprises an aluminum oxide carrier and platinum nanoparticles loaded on the aluminum oxide carrier; the platinum nanoparticles comprise first particles with the size of 0.3-1 nm, second particles with the size of 1.01-1.6 nm and third particles with the size of 1.61-10 nm, the content of the first particles is smaller than or equal to 10%, the content of the second particles is larger than or equal to 65%, and the content of the third particles is smaller than or equal to 25%. The concentration of by-products in the product is controlled by reasonably adjusting the microstructure of the catalyst and regulating and controlling the reaction path of dehydrogenation catalysis, and the method has important significance on blocking generation of carbon on the surface of the catalyst and improving the operation stability of the catalyst. For example, in the dehydrogenation reaction of methylcyclohexane, the content of cyclopentane byproducts in the product is less than or equal to 0.015%, and the reaction conversion rate of methylcyclohexane is greater than 95%.

The present invention relates to a process for the preparation of (1R, 2S, 5R)-1-amino-5-[2-(dihydroxyboryl) ethyl]-2-[(dimethylamino) methyl] cyclohexane-1-carboxylic acid in the form A of crystal. The present invention further relates to methyl (1R, 2R, 4R)-2-acetamido-2-(tert-butylcarbamoyl)-4-(2-(4, 4, 5, 5-tetramethyl-1, 3, 2-dioxacyclopentboran-2-yl) ethyl) cyclohexane-1-formate, which is an intermediate in the process.

The invention relates to a method for improving the dehydrogenation performance of a methylcyclohexane catalyst by changing a heating mode. According to the method, current passes through honeycomb-shaped silicon carbide with certain resistance, so that the honeycomb-shaped silicon carbide is directly heated, and the heating mode that a traditional muffle furnace carries out indirect conduction through air and a reaction tube wall is replaced. The change of the heating mode not only improves the heat transfer rate, but also causes the change of the self state of the catalyst due to different heat conduction paths. Specifically, current passes through the honeycomb silicon carbide to make the honeycomb silicon carbide in an electron-rich state. In the reaction process, electrons of silicon carbide in the state can generate an extrusion effect on electrons of platinum (Pt) in the Pt-coated Al2O3 catalyst placed in honeycomb holes of the silicon carbide, so that the catalytic activity is enhanced. In addition, in the reduction process of the catalyst, current can promote dissociation of hydrogen through silicon carbide, and a large number of hydroxyl radicals are induced to be generated on the surface of the catalyst; hydroxides can be used as channels for rapid migration of platinum species, and dispersion of platinum is effectively promoted.

Resins for use in toys and methods for making the same are provided. In preferred embodiments, the resins comprise 30% to 55% w / w of Ethoxylated (10) Bisphenol A Diacrylate; 20% to 35% w / w of 1,3-Hexanediol, 2-ethyl-, polymer with 1,6-diisocyanatohexane, 2-hydroxyethyl acrylate- and propylene glycol monoacrylate-blocked; 20% to 30% w / w of Hexanedioic acid, polymer with 1,2-ethanediol and 5-isocyanato-1-(isocyanatometheyl)-1,3,3-trimethylcyclohexane, 2-hydroxyethyl acrylate-blocked; 1.9%±0.5% w / w of 1-Hydroxycyclohexyl phenyl ketone; 0.43%±0.05% w / w of Ethyl trimethylbenzoyl phenylphosphinate; 0.07±0.05% w / w of Diphenyl (2, 4, 6-trimethyl benzoyl) phosphine oxide; and less than 0.19% w / w of 2-hydroxyethyl acrylate.

The polyurethane elastomer is a polyurethane elastomer comprising a reaction product of an isocyanate group terminated prepolymer and a curing agent. The isocyanate group-terminated prepolymer includes a reaction product of a polyisocyanate component including bis (isocyanatomethyl) cyclohexane and a polyol component including a high molecular weight polyol and a low molecular weight polyol. And the low molecular weight polyhydric alcohol comprises 1, 4-butanediol.

The invention provides insulation paste for solar cells and a preparation method and application thereof, and relates to the technical field of insulation paste for solar cells, and the insulation paste is prepared from the following raw materials: acrylic acid modified epoxy resin, a monomer, a photoinitiator, a coupling agent and a flatting agent; wherein the acrylic acid modified epoxy resin is prepared from the following raw materials: 1, 3-bis (N, N-diglycidyl aminomethyl) cyclohexane and a carboxylic acid reaction component. The insulating glue for the solar cell provided by the invention has the advantages of lower viscosity, high reaction activity and excellent edge covering and gluing performance, the edge film surface is neat, the coating thickness (10-15 microns) can be thinner and is close to the height (10-12 microns) of an electroplated grid line, and after cell pieces are stacked and packaged, the fragment rate is greatly reduced.

The invention discloses a high-adhesion anti-ultraviolet acrylic coating for a PC glass plate and a preparation method of the high-adhesion anti-ultraviolet acrylic coating, and belongs to the technical field of water-based paints.A self-synthesized composite ultraviolet light absorber is added in the coating preparation process, and the surface of the composite ultraviolet light absorber is of a special copper-zinc nanoneedle rough and porous structure; the coating can be endowed with good bonding strength and conductivity, static electricity caused by easy surface friction and dry environment when the PC glass plate is used as a sunshine roof is avoided, and dust and oil stain adsorption is avoided; a copper film on the surface of a copper-plated titanium dioxide microsphere is used as a site, oxidation treatment is carried out through ammonium sulfate and a sodium hydroxide solution, then electrochemical reduction is carried out on the copper-plated titanium dioxide microsphere and zinc chloride, the copper-zinc nanoneedle composite microsphere with the needle tip morphology is formed, the morphology has more active sites, enrichment of local reactants and reaction intermediates is facilitated, and the reaction efficiency is improved. The subsequent adsorption and coating of the 2-chloro-4-nitrophenyl oxyethyl methyl cyclohexane are facilitated.

The present invention relates to a curing agent for epoxy resins, which contains 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane and N-benzyl-1,2-ethylenediamine in such amounts that the ratio of the number of their amine hydrogens is in the range of 90 / 10 to 20 / 80. The curing agent according to the invention enables an epoxy resin composition suitable as a coating material, which has excellent processability and rapid curing, has almost no defects caused by clouding even under wet and cold conditions, and has a particularly high hardness, a high glass transition temperature and a surprisingly low yellowing tendency after curing.

The invention discloses an industrial production method of 2, 5-dimethyl-2, 5-hexanediol, which belongs to the technical field of chemical engineering, and comprises the following steps: adding acetylene and acetone as raw materials and a catalyst into a solvent, carrying out ethynylation condensation reaction to prepare hexynediol, and then separating by alkali liquor, neutralizing an organic phase, evaporating and recycling the solvent, washing with water, concentrating, centrifuging and vaporizing to obtain 2, 5-dimethyl-2, 5-hexanediol. The preparation method comprises the following steps: firstly, preparing 2, 5-dimethyl-3-hexyne-2, 5-diol, and finally, preparing 2, 5-dimethyl-3-hexyne-2, 5-diol, and selecting one of cyclohexane, methyl cyclohexane, methyl tert-butyl ether and ethyl tert-butyl ether as a solvent for the ethynylation condensation reaction; according to the method, the problems that the viscosity of a suspension liquid in the ethynylation condensation reaction process in 2, 5-dimethyl-2, 5-diol production is high, reaction heat is not easy to exchange, and the reaction effect is influenced are solved, and the problems that a traditional solvent is toxic to human and pollutes the environment, and safety and environmental protection risks and management cost are high in production are also solved.

The invention discloses an activated carbon adsorption saturation judgment and waste gas emission detection method for tire vulcanization VOCs (Volatile Organic Compounds). The method comprises the following steps: detecting the concentration of target pollutants at an inlet and an outlet of an adsorption bed for adsorbing the tire vulcanization VOCs by adopting a cobalt-doped zinc oxide semiconductor gas sensitive sensor; when the concentration of the target pollutant is increased to the preset concentration, the VOCs outlet concentration does not meet the emission limit value; when the adsorption efficiency of the activated carbon to the target pollutants is lower than a preset value, the adsorption capacity of the activated carbon for adsorbing the tire vulcanization VOCs reaches a saturated state, and the activated carbon needs to be replaced or regenerated; wherein the target pollutants comprise at least one of acetone, cyclohexane and methyl cyclohexane. Before the VOCs are discharged, the concentration of the target pollutants at the outlet of the purification equipment is detected to judge whether the VOCs produced by tire vulcanization really reach the standard or not and judge the adsorption saturation degree of the activated carbon.

The present invention relates to a polyester copolymer having excellent physical properties and biodegradability while having a high content of recycled raw materials. Specifically, the present invention relates to a polyester copolymer, which comprises a repeating unit derived from recycled raw materials, repeating units derived from a dicarboxylic acid component, and repeating units derived from a diol component, the dicarboxylic acid component comprising cyclohexanedicarboxylic acid (CHDA), dimethylcyclohexanedicarboxylate (DMCD), or a combination thereof, is environmentally friendly because of the high content of recycled raw materials, and has excellent physical properties and biodegradability.

The invention provides a preparation method and application of low-crystallization-velocity polypropylene random copolymer based on in-situ synthesis modification, and the preparation method comprises the following steps: pre-polymerizing propylene and a vinyl compound to obtain a pre-polymer; the vinyl compound is selected from at least one of vinyl cyclopentane, vinyl-2-methyl cyclohexane, 3-methyl-1-butene, 3-ethyl-1-hexene, 3-methyl-1-pentene and styrene, and the vinyl compound is selected from at least one of vinyl cyclopentane, vinyl-2-methyl cyclohexane, 3-methyl-1-butene, 3-ethyl-1-hexene, 3-methyl-1-pentene and styrene; carrying out polymerization reaction on the prepolymer, propylene, ethylene and hydrogen to obtain ethylene-propylene random copolymer polypropylene resin powder; uniformly mixing the ethylene-propylene random copolymer polypropylene resin powder, the antioxidant, the halogen absorbing agent, the antistatic agent and the nucleating agent; and extruding the obtained mixture to obtain the polypropylene random copolymer with low crystallization speed. According to the invention, the vinyl compound is introduced in the pre-polymerization stage, so that the polypropylene random copolymer has lower isotacticity and slowed down crystallization speed, and the crystallization behaviors of the surface and the interior of an obtained product tend to be consistent in the injection molding process of the polypropylene random copolymer.

The application belongs to the technical field of medicine synthesis, and particularly relates to an intermediate compound of edoxaban. The application takes 2-bromo-5-methyl-3a, 4, 5, 6, 7, 7a-hexahydrothiazolo[5, 4-c] pyridine as a starting material, and a lactam product is obtained by undergoing a carbonylation reaction with (3R, 4R)-3-amino-4-hydroxy-N, N-dimethylcyclohexane-1-carboxamide under the action of a catalyst, and the obtained lactam product undergoes a Mitsunobu reaction with N-(4-chlorophenyl) oxamide to obtain edoxaban. The preparation method of edoxaban provided by the application introduces a lactam by using a copper-catalyzed carbonylation reaction, and the whole synthesis method is simple in operation, high in reaction yield and purity; can effectively avoid the addition of n-butyllithium and low-temperature operation required by the carboxylation in the prior art, improve the operation safety, and has the advantages of mild use conditions, high conversion rate and simple operation.

A reinforced polycarbonate composition comprising 50-95 wt % of a poly(aliphatic ester-carbonate); 5-40 wt % of a high heat copolycarbonate comprising high heat carbonate units derived from 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethyl-cyclohexane, N-phenyl phenolphthalein bisphenol, 4,4-(1-phenylethylidene)bisphenol, 4,4-(3,3-dimethyl-2,2-dihydro-1H-indene-1,1-diyl)diphenol, 1,1-bis(4-hydroxyphenyl)cyclododecane, 3,8-dihydroxy-5a,10b-diphenyl-coumarano-2′,3′,2,3-coumarane, or a combination thereof, preferably 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethyl-cyclohexane, N-phenyl phenolphthalein bisphenol, or a combination thereof, and optionally comprising low heat carbonate units; 0.1-0.8 wt % of a C1-16 alkyl sulfonate salt flame retardant; 0.1-0.8 wt % of an anti-drip agent; 5-35 wt % glass fibers; wherein each amount is based on the total weight of the reinforced polycarbonate composition, which sums to 100 wt %.

The present application relates to the technical field of electrochemical energy storage materials and lithium metal batteries, and particularly relates to a functionalized crosslinked in-situ polymerization gel electrolyte, a preparation method and application thereof, and a lithium metal battery, wherein the preparation method successfully constructs a three-dimensional crosslinked gel polymer electrolyte by introducing 1,3-bis(N,N-diglycidyl aminomethyl) cyclohexane into a 1,3-dioxolane in-situ polymerization system. The gel electrolyte has good formability, mechanical stability and flow resistance, and can be in-situ solidified after fully infiltrating the electrode and the separator in the battery, thereby improving the electrode / electrolyte interface contact. Since the in-situ polymerization gel electrolyte has good thermal stability, a wide electrochemical stability window, a high lithium ion transference number and good lithium metal interface stability, the rate performance, long cycle performance and high-voltage working stability of the battery are effectively improved, and the cycle life, safety and practical application potential of the lithium metal battery are improved.

The present invention relates to a polyester copolymer comprising: a repeating unit A derived from a first dicarboxylic acid component comprising terephthalic acid (TPA) or dimethyl terephthalate (DMT); a repeating unit B derived from a second dicarboxylic acid component comprising dimethyl cyclohexane dicarboxylate (DMCD); and a repeating unit C derived from a diol component comprising a C2-C6 alkanediol compound, wherein the repeating unit B is included in an amount of 40 mol % or less based on the total number of moles of repeating units derived from all the dicarboxylic acid components. The polyester copolymer is environmentally friendly and has excellent mechanical properties, optical properties, and processability.

The present invention belongs to the technical field of organic synthesis. Disclosed is a preparation method for bisphenol A bis(2-hydroxyethyl) ether. The specific steps of the preparation method are as follows: adding bisphenol A, a mixed acetate catalyst and a solvent into a reactor; starting stirring and performing replacement by nitrogen, raising the temperature to a reaction temperature, and then starting to feed ethylene oxide; after the addition of ethylene oxide is completed, maintaining the temperature and continuing the reaction until the pressure no longer decreases; cooling same to a desolventization temperature, performing desolventization until no more solvent comes out, then cooling same and degassing same, and discharging same to obtain the bisphenol A bis(2-hydroxyethyl) ether. The mixed acetate catalyst consists of calcium acetate, magnesium acetate and barium acetate; and the solvent is methyl cyclohexane. The preparation method of the present invention uses specific mixed acetates as a catalyst and methyl cyclohexane as a solvent, so that an excellent catalytic effect is achieved and the prepared bisphenol A bis(2-hydroxyethyl) ether is endowed with high purity, a low hydroxyl value and light color, and the solvent has low toxicity and is easy to recycle.

The present invention relates to a method for preparing (1R,2S,5R)-1-amino-5-[2-(dihydroxyboranyl)ethyl]-2-[(dimethylamino)methyl]cyclohexane-1-carboxylic acid in anhydrous crystalline form A. The present invention further relates to methyl(1R,2R,4R)-2-acetamido-2-(tert-butylcarbamoyl)-4-(2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)ethyl)cyclohexane-1-carboxylate, an intermediate of the method.