Methods for preparing isotopically modified 1,4-diene systems from non-isotopically modified 1,4-dienes involve selective oxidation of one or more bis-allylic position(s), or the preparation of isotopically modified 1,4-diene systems via trapping pi-allylic complexes with a source of deuterium or tritium. Such methods are useful for preparing isotopically modified polyunsaturated lipid including polyunsaturated fatty acids and polyunsaturated fatty acid derivatives.

Methods for preparing isotopically modified 1,4-diene systems from non-isotopically modified 1,4-dienes involve selective oxidation of one or more bis-allylic position(s), or the preparation of isotopically modified 1,4-diene systems via trapping pi-allylic complexes with a source of deuterium or tritium. Such methods are useful for preparing isotopically modified polyunsaturated lipid including polyunsaturated fatty acids and polyunsaturated fatty acid derivatives.

The present invention relates to a method for preparing p-menthane-3,8-diol, characterised in that it comprises the following steps:

a. preparation of an aqueous solution comprising between 0.05% and 5% by mass, preferably between 0.05% and 2% by mass, preferentially between 0.05% and 1% by mass, even more preferentially between 0.05% and 0.5% by mass of an ammonium salt, the said ammonium salt being characterised in that it is selected from the group formed by an amino acid ammonium salt, and in particular an amino acid hydrochloride, a vitamin B ammonium salt, and in particular a vitamin B hydrochloride, an ammonium salt of an amino acid ester, and an ammonium salt of a vitamin B ester, or is defined by the following formula (I):

##STR00001##

wherein R.sub.1 represents a benzyl, optionally substituted, or R.sub.1 represents an alkyl, either linear or branched, optionally cyclical, saturated or unsaturated, optionally substituted, comprising from 1 to 10 carbon atoms, preferably from 1 to 6 carbon atoms, preferentially from 2 to 4 carbon atoms, and R.sub.2, R.sub.3 and R.sub.4 represent a hydrogen or a methyl group, and X represents a chlorine atom, bromine atom or an OR′ group, R′ being an alkyl group comprising from 1 to 10 carbon atoms,

b. adding of citronellal to the aqueous solution obtained in the step a), and obtaining a mixture;

c. stirring and heating of the mixture obtained in the step b);

d. decanting of the reaction medium obtained at the end of step c) and obtaining at least two phases; and

e. separation of the said at least two phases obtained in the step d), and obtaining at least one aqueous phase and at least one organic phase, the said organic phase comprising at least p-menthane-3,8-diol.

The present invention relates to a method for preparing p-menthane-3,8-diol, characterised in that it comprises the following steps:

a. preparation of an aqueous solution comprising between 0.05% and 5% by mass, preferably between 0.05% and 2% by mass, preferentially between 0.05% and 1% by mass, even more preferentially between 0.05% and 0.5% by mass of an ammonium salt, the said ammonium salt being characterised in that it is selected from the group formed by an amino acid ammonium salt, and in particular an amino acid hydrochloride, a vitamin B ammonium salt, and in particular a vitamin B hydrochloride, an ammonium salt of an amino acid ester, and an ammonium salt of a vitamin B ester, or is defined by the following formula (I):

##STR00001##

wherein R.sub.1 represents a benzyl, optionally substituted, or R.sub.1 represents an alkyl, either linear or branched, optionally cyclical, saturated or unsaturated, optionally substituted, comprising from 1 to 10 carbon atoms, preferably from 1 to 6 carbon atoms, preferentially from 2 to 4 carbon atoms, and R.sub.2, R.sub.3 and R.sub.4 represent a hydrogen or a methyl group, and X represents a chlorine atom, bromine atom or an OR′ group, R′ being an alkyl group comprising from 1 to 10 carbon atoms,

b. adding of citronellal to the aqueous solution obtained in the step a), and obtaining a mixture;

c. stirring and heating of the mixture obtained in the step b);

d. decanting of the reaction medium obtained at the end of step c) and obtaining at least two phases; and

e. separation of the said at least two phases obtained in the step d), and obtaining at least one aqueous phase and at least one organic phase, the said organic phase comprising at least p-menthane-3,8-diol.

A system and a process for co-producing dimethyl carbonate and ethylene glycol. The system comprises an interconnected ethylene carbonate preparation unit and an ethylene carbonate alcoholysis unit. The ethylene carbonate preparation unit comprises a fixed bed reactor and a light-component stripping column connected to each other. The fixed bed reactor is filled with a supported ionic liquid catalyst. The process comprises the steps of: reacting carbon dioxide and ethylene oxide as raw materials in the fixed bed reactor to produce ethylene carbonate, purifying the ethylene carbonate and then mixing it with an alcoholysis reaction catalyst, and reacting the mixture with methanol in a reactive distillation tower, producing dimethyl carbonate and ethylene glycol. The process increases the conversion rate of ethylene oxide and avoids the need for a process of separating conventional homogeneous catalysts from ethylene carbonate, thereby reducing process energy consumption and simplifying process procedures.

Methods for preparing isotopically modified 1,4-diene systems from non-isotopically modified 1,4-dienes involve selective oxidation of one or more bis-allylic position(s), or the preparation of isotopically modified 1,4-diene systems via trapping pi-allylic complexes with a source of deuterium or tritium. Such methods are useful for preparing isotopically modified polyunsaturated lipid including polyunsaturated fatty acids and polyunsaturated fatty acid derivatives.

Methods for preparing isotopically modified 1,4-diene systems from non-isotopically modified 1,4-dienes involve selective oxidation of one or more bis-allylic position(s), or the preparation of isotopically modified 1,4-diene systems via trapping pi-allylic complexes with a source of deuterium or tritium. Such methods are useful for preparing isotopically modified polyunsaturated lipid including polyunsaturated fatty acids and polyunsaturated fatty acid derivatives.

Methods for preparing isotopically modified 1,4-diene systems from non-isotopically modified 1,4-dienes involve selective oxidation of one or more bis-allylic position(s), or the preparation of isotopically modified 1,4-diene systems via trapping pi-allylic complexes with a source of deuterium or tritium. Such methods are useful for preparing isotopically modified polyunsaturated lipid including polyunsaturated fatty acids and polyunsaturated fatty acid derivatives.

An aim of the present disclosure is to provide a method for producing a fluoroalkoxide, said method being more useful than conventional methods, and the like. The aim can be achieved by a method for producing a compound represented by the following formula (1):

##STR00001## (wherein R.sup.1 is a fluoroalkyl group optionally containing an oxygen atom between carbon atoms, or a fluoroalkoxy group optionally containing an oxygen atom between carbon atoms, and each R.sup.2 is identical to or different from each other and is a hydrocarbon group), the method comprising the step of reacting a compound represented by the following formula (2):

##STR00002## with a compound represented by the following formula (3):

.sup.⊖F.sup.⊕NR.sup.2).sub.4  (3).

An aim of the present disclosure is to provide a method for producing a fluoroalkoxide, said method being more useful than conventional methods, and the like. The aim can be achieved by a method for producing a compound represented by the following formula (1):

##STR00001## (wherein R.sup.1 is a fluoroalkyl group optionally containing an oxygen atom between carbon atoms, or a fluoroalkoxy group optionally containing an oxygen atom between carbon atoms, and each R.sup.2 is identical to or different from each other and is a hydrocarbon group), the method comprising the step of reacting a compound represented by the following formula (2):

##STR00002## with a compound represented by the following formula (3):

.sup.⊖F.sup.⊕NR.sup.2).sub.4  (3).