92 results about "Dioxolane" patented technology

The invention discloses a phenanthridine-6-formaldehyde derivative and a preparation method and application thereof.The preparation method comprises the steps that 2, 4, 5, 6-tetra (9-carbazolyl)-isophthalonitrile serves as a photocatalyst, 1-azabicyclo [2.2. 2] octane serves as a hydrogen atom transfer catalyst, a biphenyl isocyanide compound, the photocatalyst, the hydrogen atom transfer catalyst and an alkali additive are jointly dissolved in 1, 3-dioxolane, the mixture is stirred to be uniform, and the phenanthridine-6-formaldehyde derivative is obtained. And carrying out free radical tandem cyclization and acid-catalyzed hydrolysis reaction to obtain the phenanthridine-6-formaldehyde derivative. The invention also provides a specific reaction equation. According to the developed synthesis method of the phenanthridine-6-formaldehyde derivative, the compound can be efficiently and conveniently prepared, the technical bottlenecks of harsh reaction conditions and tedious steps in a traditional process are successfully overcome, raw materials which are low in price and easy to obtain are adopted, operation is carried out under mild conditions, the synthesis method has the outstanding advantages of being high in yield, safe and simple to operate, environmentally friendly and the like, and the method is suitable for industrial production. Good industrial application potential is shown.

The invention discloses a low-temperature high-conductivity composite solid-state electrolyte membrane and a preparation method and application thereof, and relates to the technical field of solid-state lithium battery materials, the low-temperature high-conductivity composite solid-state electrolyte membrane comprises: a polymer matrix composed of poly (1, 3-dioxolame) and a polyvinylidene fluoride-hexafluoropropylene copolymer; the ion conduction network is composed of a metal organic framework filler with the surface modified with-SO3Li groups and sulfonic acid lithiated carbon nanotubes arranged in the axial direction of the polymer matrix; a first anti-freezing interface layer and a second anti-freezing interface layer are arranged on the surfaces of the two opposite sides of the polymer matrix, and the first anti-freezing interface layer and the second anti-freezing interface layer are butanedinitrile-glutaronitrile eutectic plastic crystal layers composed of butanedinitrile, glutaronitrile, lithium salt and a nano reinforcing agent respectively. The solid electrolyte is suitable for polar scientific investigation equipment, spacecrafts and other low-temperature environments, and solves the industrial problems of sharp increase of low-temperature grain boundary impedance and interface contact failure of the traditional solid electrolyte.

This application provides a method for preparing compound I-b or a pharmaceutically acceptable salt thereof, wherein (S)-N-methylamino-1-(2-thiophene)-1-propanol reacts with 4-fluorobenzo[1,3]dioxolane in a system containing sodium hydride and potassium benzoate to obtain compound I-b. This method has short steps, mild reaction conditions, and is simple to operate, making it suitable for industrial scale-up; moreover, the obtained product has high purity and low isomer content.

Methods for coating electrodes, particularly anodes, more particularly lithium anodes in batteries. The coating material obtained by the methods, involves the ring-opening polymerization of dioxolane (DOL) monomers in presence of suitable polymerization initiators, crosslinkers and optional further additives. The so-obtained coating material displays advantageous features such as fast lithium ions diffusion and high conductivity, high elastic modulus blocking dendrite formation, high flexibility, scalability, controllable thickness of the coating material and homogeneity on the anode surface. The corresponding electrochemical cells and / or batteries comprising the coating material, are characterized by improved stability during the cell / battery cycling.

The application discloses a kind of in-situ gel preparation methods, belong to lithium metal battery technical field.The method introduces trace initiator to make 1,3-dioxolane DOL in electrolyte occur ring-opening polymerization reaction, by forming DOL crosslinking in advance, realize liquid ether-based electrolyte in-situ solidification on the surface of lithium negative electrode.After forming gel phase, inject electrolyte in soft pack battery of gel phase, construct gel phase@liquid phase two-phase system.By controlling the ratio of electrolyte and poly-DOL, realize the gradient solidification of ether-based electrolyte in battery, adjust the mechanical properties of gel electrolyte.There is intermolecular interaction between poly-DOL and lithium salt anion, significantly improve the ionic conductivity and lithium ion transference number of gel electrolyte, the in-situ gel phase formed has good interface compatibility with lithium negative electrode, and the growth of lithium dendrite is inhibited.This in-situ gel preparation method is low in cost and easy to operate, and is a simple method to realize high capacity and high cycle stability of lithium metal battery.

The invention provides a synthesis method of a quaternary cycloalkane modified O-glucoside compound shown in formula 3, in the presence of a catalyst, a sugar compound shown in formula 1 with exposed hydroxyl and a quaternary tension ring substrate compound shown in formula 2 are subjected to nucleophilic addition reaction in an organic solvent to prepare the quaternary cycloalkane modified O-glucoside compound shown in formula 3: X is H, CF3 or Cl; a is a dioxolane type compound or a pyran type compound; the catalyst is phosphazene base P4-t-Bu, and the specific structural formula is shown in the specification.

An in-situ polymerization dioxolane polymer solid electrolyte, a fluorinated magnesium interface layer, a battery and a preparation method thereof, 1,3-dioxolane, lithium salt and magnesium-containing montmorillonite are uniformly mixed to obtain a mixed solution, then the mixed solution is immersed into a support, matched with a lithium metal negative electrode and a positive electrode to assemble a full battery, and placed for a period of time, and a polymerized dioxolane composite polymer solid electrolyte is prepared through an in-situ polymerization reaction. The magnesium ions spontaneously aggregated on the surface of the montmorillonite compete with the lithium salt anions for coordination, regulate the coordination environment of lithium ions in the electrolyte, increase the number of free lithium ions, and thus improve the ionic conductivity of the electrolyte. In addition, the magnesium ions and the lithium salt anion ligands decompose at the positive and negative electrode interface to participate in the formation of the interface layer, producing an inorganic component-rich interface layer (CEI and SEI) containing fluorinated magnesium, which has a high Young's modulus and fast lithium ion transport kinetics, is beneficial to the rapid transport of lithium ions and improves the stability of the electrolyte and the positive and negative electrode interface, and thus has a good application prospect.

The invention provides an organic-inorganic hybrid solid-state polymer electrolyte coated high-nickel positive electrode material as well as a preparation method and application thereof, and relates to the technical field of all-solid-state lithium batteries. The high-nickel positive electrode material coated with the organic-inorganic hybrid solid polymer electrolyte comprises an inner core and an organic-inorganic hybrid coating layer coated on the surface of the inner core, the inner core is made of a high-nickel positive electrode material; the organic-inorganic hybrid coating layer comprises a ring-opening copolymer of maleic anhydride and 1, 3-dioxolame, and Li3PO4 nanocrystals are embedded into the ring-opening copolymer of maleic anhydride and 1, 3-dioxolame in situ. According to the invention, a flexible and compact coating layer with ionic conductivity is constructed on the surface of the high-nickel positive electrode material, so that the problems of violent interface side reaction, large interface impedance and poor cycling stability existing between the high-nickel positive electrode material and sulfide solid electrolyte are solved; therefore, the electrochemical performance of the material in a sulfide all-solid-state lithium battery is remarkably improved.

The invention belongs to the technical field of photo-curing materials, and particularly relates to a photo-curing adhesive for 3D printing and a preparation method thereof.The photo-curing adhesive for 3D printing is prepared from, by weight, 30-70 parts of isocyanate-group-free polyurethane modified acrylate resin, 30-70 parts of a curing agent, 1-5 parts of a curing agent, 1-5 parts of a curing agent and 1-5 parts of a curing agent. 20 to 40 parts of a bio-based acrylate monomer; 10-30 parts of a low surface tension acrylate monomer; and 1-7 parts of a photoinitiator. According to the invention, the polyurethane acrylate resin synthesized from DOMA (2-oxo-1, 3-dioxolane-4-yl methyl methacrylate) and polyether amine through a non-isocyanate path is adopted, so that the possibility of existence of free isocyanate monomers is thoroughly eliminated from the aspect of molecular design, and the safety in production and use processes is remarkably improved.

The application relates to the technical field of propiconazole synthesis, in particular to a method for synthesizing propiconazole by using ionic liquid catalysis and a solvent-free method, which comprises the following steps: S1, under the condition of room temperature, 1,2,4-triazole sodium or 1,2,4-triazole potassium and 1-4 carbon atom organic alcohol solvent are mixed, a quaternary ammonium salt is added, reflux is carried out for 10 hours, and insoluble substances are removed through filtration; 1-4 carbon atom organic alcohol solvent is removed through distillation, and transparent colorless 1,2,4-triazole-quaternary ammonium ionic liquid is obtained; S2, 2-(2,4-dichlorophenyl)-2-bromomethyl-4-propyl-1,3-dioxolane is mixed with the 1,2,4-triazole-quaternary ammonium ionic liquid, the temperature is increased to 150-160 DEG C, reaction is carried out for 10-15 hours, the temperature is decreased, post-treatment is carried out, and propiconazole with a purity of more than 98% is obtained. The method has the advantages that impurities are reduced, the purity and yield of propiconazole are improved, post-treatment is simple, and wastewater is extremely small, and is a valuable method for industrialization popularization and application.

Disclosed are novel fused mescaline derivative compounds, notably substituted ethylamine fused heterocyclic mescaline derivatives, including substituted ethylamine fused dioxolane mescaline derivatives, and pharmaceutical and recreational drug formulations containing the same. Methods of making and using these compounds are also disclosed.

The invention discloses a lithium ion electrolyte and a preparation method thereof as well as a lithium ion battery and a preparation method thereof. The lithium ion electrolyte comprises the following components: a lithium salt with the concentration of 1-1.5 mol / L, a fluoroborate-containing additive with the mass percent of 1-5%, a surfactant with the mass percent of 0.05-1% and the balance of a mixed solvent system, the mixed solvent system comprises tris (2, 2, 2-trifluoroethyl) phosphate, 1, 3-dioxolame and tetrahydrofuran; the preparation method of the lithium ion electrolyte comprises the following steps: preparing a mixed solvent system, adding a lithium salt and stirring; adding a fluoroborate-containing additive and a surfactant, stirring, and filtering; the lithium ion battery comprises a lithium ion electrolyte, a positive plate and a negative plate, the preparation method of the lithium ion battery comprises the following steps: assembling the positive plate, the diaphragm and the negative plate into a battery cell, and injecting the lithium ion electrolyte into the battery cell. The low-temperature discharge performance and the low-temperature cycle performance of the lithium ion battery are improved.

A method for manufacturing solketal ((2,2-Dimethyl-1,3-dioxolan-4-yl)methanol) includes: (1) milling starting reagents, including at least: glycerol, a catalyst selected from a hard Lewis acid including at least one transition metal, and acetone, the molar ratio (glycerol):(acetone) being less than or equal to 0.8; preferably less than or equal to 0.7, at an ambient temperature greater than or equal to 50° C., preferably greater than or equal to 56° C., in a three-dimensional microbead mill in a liquid phase for a residence time less than or equal to 15 minutes, preferably less than or equal to 10 minutes, and in particular less than or equal to 5 minutes; (2) recovering, as output from the mill, a final composition including solketal and, where appropriate, one or more sub-products corresponding to the starting reagents that have not reacted and / or to 1,3-O-isopropylidene-glycerol, and (3) optionally, separating the solketal from the one or more sub-products.

The invention relates to a supramolecular semi-interpenetrating polymer network electrolyte and a preparation method and application thereof.The supramolecular semi-interpenetrating polymer network electrolyte is prepared from, by weight, 150-300 parts of polytetrahydrofuran, 150-300 parts of 18-crown ether-6, 40-60 parts of dicyclohexylmethane 4, 4 '-diisocyanate, 2, 2'-(1, 4-phenyl)-bis [4-(4-hydroxybutyl)-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4- The composite material is prepared from the following components in parts by weight: 32 to 48 parts of 1, 2-dioxaborolane], 1 to 1.2 parts of a catalyst, 5.5 to 8.5 parts of an end-capping reagent, 1500 to 2500 parts of 1, 3-dioxolame, 500 to 840 parts of lithium bis (trifluoromethylsulfonyl) imide, 23 to 38 parts of scandium trifluoromethanesulfonate and 15 to 25 parts of a cross-linking agent. According to the invention, a functional thermoplastic polyurethane elastomer-rotaxane is introduced into a polydioxolame matrix to form a supramolecular semi-interpenetrating network structure, so that concentration polarization and growth of lithium dendrites can be inhibited, and the cycling stability is improved.

This invention discloses an amorphous polyether composite electrolyte based on oxygen-vacancy cerium oxide nanofiller and its preparation method, relating to the field of solid-state battery technology. The preparation method of the amorphous ether composite electrolyte based on oxygen-vacancy cerium oxide nanofiller includes the following steps: mixing 1,3-dioxolane with a metal salt and an initiator in a solvent; adding oxygen-vacancy cerium oxide nanofiller to form a prepolymer solution; and under initiator conditions, polymerizing the 1,3-dioxolane in the prepolymer solution to obtain the amorphous ether composite electrolyte based on oxygen-vacancy cerium oxide nanofiller; wherein the metal salt is a lithium salt and / or a sodium salt. This invention, through the synergistic design of high-oxygen-vacancy cerium oxide nanofiller and amorphous poly(1,3-dioxolane) matrix, comprehensively improves the ionic conductivity, high-voltage resistance, fast-charging capability, and cycle stability of the composite electrolyte, providing a key material solution for the practical application of high-performance lithium / sodium-ion batteries.

The invention discloses a quasi-solid electrolyte of a sodium metal battery, a preparation method of the quasi-solid electrolyte and a quasi-solid sodium battery, and the preparation method comprises the following steps: mixing sodium bis (trifluoromethanesulfonyl) imide, sodium difluoro (oxalato) borate and dioxolane, and stirring until the mixture is completely dissolved to obtain a sodium salt solution; dissolving tin trifluoromethanesulfonate in the fluoroethylene carbonate solution to obtain an initiator solution; adding the initiator solution into the sodium salt solution, and uniformly stirring to obtain an electrolyte precursor solution; and injecting the electrolyte precursor solution into the battery, sealing, and standing at a constant temperature to obtain the quasi-solid electrolyte of the sodium metal battery. The quasi-solid sodium battery further comprises a positive electrode, a negative electrode and a diaphragm. Through the design of the internal interlocking redox regulation pair, synthesis of the quasi-solid electrolyte and in-situ construction of the stable interface layer are achieved in one step, the process is simple and efficient, and the problems that in a traditional method, interface modification steps are complex, and compatibility with body electrolyte is poor are solved.

The invention relates to the technical field of energy storage, in particular to a gel electrolyte, and an electrochemical device and electronic equipment comprising the same, and the gel electrolyte is obtained by gelation reaction of a precursor solution comprising 1, 3-dioxolane, boron trifluoride diethyl etherate, lithium perchlorate and fluoroethylene carbonate. The gel electrolyte provided by the invention can realize a 5.4 V electrochemical stable window, and has high ionic conductivity and excellent cycle performance.

The invention discloses a flame-retardant gel polymer electrolyte and a preparation method and application thereof, and belongs to the technical field of supercapacitors. The method comprises the following steps: adding iodine diethyl methyl phosphate and 1, 3-propane sultone into an organic solvent containing 1, 3-dioxolane, and uniformly mixing to obtain a mixed solution; adding lithium salt into the mixed solution to obtain a precursor solution; and dropwise adding the precursor solution on the surface of an electrode to assemble a supercapacitor, and heating to form the flame-retardant gel polymer electrolyte on the surface of the electrode in situ. According to the flame-retardant gel polymer electrolyte prepared by the method, the flame-retardant characteristic of the electrolyte can be remarkably improved, the combustion risk is fundamentally eradicated, a good solid-liquid mixed interface can be formed with an electrode, and high ionic conductivity and low interface impedance are guaranteed.

The invention discloses a polymer gel electrolyte, a preparation method and application. According to the invention, 1, 3-dioxolame and a hexa-(epoxypropyl) cyclotriphosphazene cross-linking agent are subjected to in-situ polymerization under the initiation of lithium bis (trifluoromethanesulfonimide) and lithium difluoro (oxalato) borate to form a cross-linked polymer network structure, and ethylene carbonate, dimethyl carbonate and ethyoxyl (pentafluoro) cyclotriphosphazene liquid phase components are anchored in the polymer network. The polymer gel electrolyte prepared by the invention not only has the advantage of intrinsic flame retardance, but also has the performance of high ionic conductivity, and the service life of a lithium battery is prolonged.

The invention discloses a dianion salt-based magnesium fuel cell electrolyte and a preparation method, and belongs to the technical field of magnesium fuel cells, the electrolyte is composed of dianion composite magnesium salt, propylene carbonate (PC), tetrahydrofuran (THF), magnesium fluoride (MgF) nanoparticles, 1, 3-dioxolane (DOL), diethylene glycol dimethyl ether (G2) and trimethyl phosphate (TMP) according to a specific mass percentage, and the dianion salt-based magnesium fuel cell electrolyte is prepared from dianion composite magnesium salt, propylene carbonate (PC), tetrahydrofuran (THF), magnesium fluoride (MgF) nanoparticles, 1, 3-dioxolane (DOL), diethylene glycol dimethyl ether (G2) and trimethyl phosphate (TMP) according to a specific mass percentage. The mass ratio is 1: (1.6-2.0). The preparation method comprises the four steps of composite salt preparation, solvent dehydration, salt dissolution and additive mixing, and the ionic conductivity and thermal stability of the electrolyte are improved through specific ultrasonic parameters, dehydration conditions and annealing treatment.

This invention relates to the field of electrochemical energy storage materials and lithium metal battery technology, specifically to an in-situ polymerized solid electrolyte, its preparation method and application, and lithium metal batteries. This in-situ polymerized solid electrolyte is prepared by heating a ring-opening polymerization reaction using 1,3-dioxolane and 1,1,1-trifluoro-2,3-epoxypropane as reactants, sodium thiosulfate as an initiator, and lithium salt and plasticizer fluoroethylene carbonate as a precursor solution. This electrolyte possesses numerous amorphous regions, which is beneficial for ion transport, enabling the formation of a self-supporting dense structure. It also ensures close contact with the electrode, resulting in a pure interface that effectively reduces interfacial impedance and avoids side reactions at the electrode interface. Furthermore, it enhances oxidation resistance, broadens the electrochemical window, and inhibits dendrite growth. While achieving good mechanical properties, it also improves the cycle stability and safety performance of the battery. It has excellent application prospects in lithium metal batteries, lithium-ion batteries, solid-state energy storage systems, or flexible electronic devices.

The invention relates to the technical field of electrolytes, in particular to a dianion salt magnesium fuel cell non-aqueous electrolyte which is composed of the following components: composite salt, a mixed solvent, magnesium fluoride (MgF) nanoparticles, 1, 3-dioxolane (DOL), diethylene glycol dimethyl ether (G2) and trimethyl phosphate (TMP). According to the invention, a composite salt system composed of magnesium trifluoromethanesulfonate and magnesium bis (trifluoromethanesulfonyl) imide is adopted, and the ion transmission capability of the electrolyte is significantly improved through a dianion synergistic effect.

The invention discloses a hydrated eutectic electrolyte and a preparation method and application thereof, and belongs to the technical field of batteries. The invention provides a mixed ligand hydration eutectic electrolyte strategy based on thermodynamic-dynamic balance. According to the strategy, through functional synergy of acetamide (Ace) and 1, 3-dioxolane (Dol), integrated regulation and control of an electrolyte liquid phase microenvironment and interface chemistry are achieved, so that side reactions are remarkably inhibited, and the electrochemical performance is comprehensively improved.

The present invention discloses a dioxolame rectification variable pressure control system, and relates to the technical field of dioxolame rectification, the dioxolame rectification variable pressure control system comprises: a pretreatment unit for performing light component removal treatment on a crude dioxolame raw material; the variable-pressure rectification unit is connected with the output end of the pretreatment unit and is used for receiving the light-component-removed material and dehydrating and purifying the light-component-removed material; the variable pressure rectification unit comprises a first rectification tower and a second rectification tower which are different in operation pressure, the tower top steam output end of the first rectification tower is connected to the feeding end of the second rectification tower after being condensed and decompressed, and the tower top output end of the second rectification tower is connected to the feeding end of the first rectification tower to form circulation; through a pressure swing distillation core process, the limitation of dioxolame-water azeotrope is successfully broken through, and the problem that a high-purity product cannot be obtained through traditional distillation is fundamentally solved.

This invention provides a 3-amino-5-phenyl-pyrazole derivative microtubule inhibitor, its preparation, and its pharmaceutical uses. The structure of the 3-amino-5-phenyl-pyrazole derivative is shown in formula (I): In formula (I), R1 is independently selected from 3,4,5-trimethoxyphenyl, 3,4-dimethoxyphenyl, or dioxolane[1,3-d]phenyl; R2 and R3 are independently selected from methyl, methoxy, fluorine, chlorine, or bromine. This type of compound not only possesses strong antitumor activity but also anti-angiogenic effects, effectively inhibiting the proliferation of tumor cells and can be used to prepare tumor proliferation inhibitors. Furthermore, it has a strong ability to inhibit microtubule aggregation, providing a novel microtubule inhibitor for inhibiting tumor cell proliferation.

The invention discloses an electrolyte of a high-specific-capacity lithium-carbon fluoride battery as well as a preparation method and application of the electrolyte. The electrolyte comprises double lithium salts and a multi-component solvent, the double lithium salt is lithium tetrafluoroborate (LiBF) and lithium bis (fluorosulfonyl) imide (LiFSI); the multi-component solvent contains tetrahydrofuran (THF) and 1, 3-dioxolane (DOL), comprises at least one of methyl acetate (MA), N, N-diethyl-2, 2, 2-trifluoroacetamide (DMTFA), ethylene carbonate (EC) and m-fluorotoluene (m-FT), and does not contain MA and DMTFA at the same time; through the combination design of the differentiated lithium salt and the multi-component solvent, the specific discharge capacity of the battery at normal temperature and low temperature is improved, the synergistic requirements of a wide temperature range, high interface stability and high safety are met, and the electrolyte keeps efficient operation within the wide temperature range.

An electrochemical apparatus includes a separator and an electrolyte solution, wherein the separator includes a base film and a first coating disposed on a surface of the base film, the first coating includes a solid-state electrolyte material, and the solid-state electrolyte material includes element Ti; the electrolyte solution includes compound I, and the compound I includes at least one selected from the group consisting of vinylene carbonate, vinyl ethylene carbonate, fluoroethylene carbonate, and 4,5-difluoro-1,3-dioxolan-2-one; and based on a mass of the electrolyte solution, a mass percentage of the compound I is P %, wherein P ranges from 0.5% to 20%, and based on a mass of the first coating, a mass percentage of the element Ti is Q %, wherein 1≤Q / P≤60.

The application discloses an environment-friendly plant-based degradable high molecular material and a preparation method thereof, and relates to the technical field of high molecular materials. In the preparation of the environment-friendly plant-based degradable high molecular material, chitosan is sequentially reacted with 5-aldehyde furan-3-boronic pinacol ester and 1-bromo-1,2,2-triphenyl ethylene to obtain modified chitosan; hesperetin is reacted with 4-(chloromethyl)-1,3-dioxolane-2-ketone to obtain functionalized hesperetin; dimethyl adipate, a phosphorus-containing diacid ester monomer and 1,6-hexanediamine are subjected to polycondensation to obtain polyamide; the polyamide is reacted with formaldehyde to obtain modified polyamide; the modified polyamide, the modified chitosan, the functionalized hesperetin and 1,5,7-triazabicyclo[4.4.0]dec-5-ene are mixed and injection molded to obtain the environment-friendly plant-based degradable high molecular material. The environment-friendly plant-based degradable high molecular material prepared by the application has excellent anti-aging, flame-retardant and mechanical properties.

The application discloses a preparation method of in-situ poly-1,3-dioxolane solid electrolyte, characterized in that a polymerization reaction of 1,3-dioxolane is in-situ initiated by using a sulfide solid electrolyte to prepare the in-situ poly-1,3-dioxolane solid electrolyte; wherein the sulfide solid electrolyte is composed of Li 3+x P 1‑ x Sn x S 4‑2x F 2x (0.05≤x≤0.2). The method can further improve the ionic conductivity of the solid electrolyte membrane by doping modification of the solid electrolyte and initiating ring-opening polymerization of 1,3-dioxolane. The in-situ poly-1,3-dioxolane solid electrolyte prepared by the method provides a channel for lithium ion transmission, resulting in cooperative migration of lithium ions and high lithium ion migration number, and improving the electrochemical performance.

The invention is directed to a process for preparing an N-substitued-2-oxazolidinone comprising reacting a cyclic carbonate or a di-alkyl carbonate with an amine-alcohol compound in the presence of a base catalyst, wherein the base catalyst has a basicity pKaH+ of above 25 as measured in acetonitrile. Especially wherein 4-methyl- 1,3-dioxolan-2-one (PC) is reacted with 2-(methylamino)ethanol (NMEA) to prepare 3-methyloxazolidin-2-one (MeOx) and propane-1, 2-diol (PG) as a byproduct or wherein 1,3-dioxolan-2-one (EC) is reacted with 2-(methylamino)ethanol (NMEA) to prepare 3-methyloxazolidin-2-one (MeOx) and ethane-1, 2-diol (ethylene glycol) as a byproduct.