There is provided a method for producing a C.sub.2-C.sub.20 fluorine-containing organic acid with reduced fluorine-free organic compound. A method for producing a C.sub.2-C.sub.20 fluorine-containing organic acid, the method including contacting a mixture containing a C.sub.2-C.sub.20 fluorine-containing organic acid and a fluorine-free organic compound with a concentrated sulfuric acid and then separating a C.sub.2-C.sub.20 fluorine-containing organic acid phase from a concentrated sulfuric acid phase. The contacting is conducted such that an amount of water present in the concentrated sulfuric acid phase is 10% by mass or less, and the C.sub.2-C.sub.20 fluorine-containing organic acid is obtained in the form of the C.sub.2-C.sub.20 fluorinated organic acid phase having a reduced content ratio of the fluorine-free organic compound compared with said mixture.

A process for preparing a compound of formula (I) HR.sup.1R.sup.2CCF.sub.2(CO)Y starting with a compound of formula (II) R.sup.1R.sup.2CCX(CO)Y or of formula (III) HR.sup.1R.sup.2CCX.sup.1X.sup.2(CO)Y placed in contact with hydrofluoric acid; R.sup.1 and R.sup.2 being independently selected from H, F, Cl, Br, I, C.sub.1-C.sub.20-alkyl, C.sub.6-C.sub.20-aryl and C.sub.2-C.sub.20-alkenyl, C.sub.3-C.sub.20-cycloalkenyl and C.sub.3-C.sub.20-cycloalkyl; X.sup.1 and X.sup.2 being independently selected from F, Cl, Br and I on condition that X.sup.1 and X.sup.2 are not simultaneously F; Y being selected from the group of H, C.sub.1-C.sub.20-alkyl, C.sub.1-C.sub.20-haloalkyl, C.sub.6-C.sub.20-aryl, OH, OR, NH.sub.2, NHR, NR.sub.2, SR, C.sub.3-C.sub.20-cycloalkyl, C.sub.3-C.sub.20-cycloalkenyl and C.sub.2-C.sub.20-alkenyl; R being independently selected from the group of C.sub.1-C.sub.20-alkyl, C.sub.6-C.sub.20-aryl and C.sub.2-C.sub.20-alkenyl, C.sub.3-C.sub.20-cycloalkenyl and C.sub.3-C.sub.20-cycloalkyl.

A process for preparing a compound of formula (I) HR.sup.1R.sup.2CCF.sub.2(CO)Y starting with a compound of formula (II) R.sup.1R.sup.2CCX(CO)Y or of formula (III) HR.sup.1R.sup.2CCX.sup.1X.sup.2(CO)Y placed in contact with hydrofluoric acid; R.sup.1 and R.sup.2 being independently selected from H, F, Cl, Br, I, C.sub.1-C.sub.20-alkyl, C.sub.6-C.sub.20-aryl and C.sub.2-C.sub.20-alkenyl, C.sub.3-C.sub.20-cycloalkenyl and C.sub.3-C.sub.20-cycloalkyl; X.sup.1 and X.sup.2 being independently selected from F, Cl, Br and I on condition that X.sup.1 and X.sup.2 are not simultaneously F; Y being selected from the group of H, C.sub.1-C.sub.20-alkyl, C.sub.1-C.sub.20-haloalkyl, C.sub.6-C.sub.20-aryl, OH, OR, NH.sub.2, NHR, NR.sub.2, SR, C.sub.3-C.sub.20-cycloalkyl, C.sub.3-C.sub.20-cycloalkenyl and C.sub.2-C.sub.20-alkenyl; R being independently selected from the group of C.sub.1-C.sub.20-alkyl, C.sub.6-C.sub.20-aryl and C.sub.2-C.sub.20-alkenyl, C.sub.3-C.sub.20-cycloalkenyl and C.sub.3-C.sub.20-cycloalkyl.

The present invention generally relates to processes for converting acrylate esters or a derivative thereof to difluoropropionic acid or a derivative thereof. This process is generally performed using fluorine gas in a hydrofluorocarbon solvent.

The present invention generally relates to processes for converting acrylate esters or a derivative thereof to difluoropropionic acid or a derivative thereof. This process is generally performed using fluorine gas in a hydrofluorocarbon solvent.

The present invention generally relates to processes for converting acrylate esters or a derivative thereof to difluoropropionic acid or a derivative thereof. This process is generally performed using fluorine gas in a hydrofluorocarbon solvent. In particular, a process for fluorinating a double bond is disclosed. This process comprises forming a reaction mixture comprising a hydrofluorocarbon solvent, fluorine gas, and a compound of formula 1 ##STR00001##
wherein R.sub.1 is hydroxy, alkoxy, chloro, or OC(O)CHCH.sub.2 to form a compound of formula 2 in a yield of at least 50% ##STR00002##
wherein R.sub.2 is hydroxy, alkoxy, chloro, OC(O)CHFCH.sub.2F, wherein the hydrofluorocarbon solvent comprises 2H,3H-decafluoropentane and the reaction mixture further comprises a fluorination agent.

The present invention generally relates to processes for converting acrylate esters or a derivative thereof to difluoropropionic acid or a derivative thereof. This process is generally performed using fluorine gas in a hydrofluorocarbon solvent. In particular, a process for fluorinating a double bond is disclosed. This process comprises forming a reaction mixture comprising a hydrofluorocarbon solvent, fluorine gas, and a compound of formula 1 ##STR00001##
wherein R.sub.1 is hydroxy, alkoxy, chloro, or OC(O)CHCH.sub.2 to form a compound of formula 2 in a yield of at least 50% ##STR00002##
wherein R.sub.2 is hydroxy, alkoxy, chloro, OC(O)CHFCH.sub.2F, wherein the hydrofluorocarbon solvent comprises 2H,3H-decafluoropentane and the reaction mixture further comprises a fluorination agent.

The present invention generally relates to processes for converting acrylate esters or a derivative thereof to difluoropropionic acid or a derivative thereof. This process is generally performed using fluorine gas in a hydrofluorocarbon solvent.

The present invention generally relates to processes for converting acrylate esters or a derivative thereof to difluoropropionic acid or a derivative thereof. This process is generally performed using fluorine gas in a hydrofluorocarbon solvent.

There is provided a method for producing a C2-C20 fluorine-containing organic acid with reduced fluorine-free organic compound. A method for producing a C2-C20 fluorine-containing organic acid, wherein the method comprises contacting a mixture containing a C2-C20 fluorine-containing organic acid and a fluorine-free organic compound with a concentrated sulfuric acid and then separating a C2-C20 fluorine-containing organic acid phase from a concentrated sulfuric acid phase, wherein the contacting is conducted such that an amount of water present in the concentrated sulfuric acid phase is 10% by mass or less, and the C2-C20 fluorine-containing organic acid is obtained in the form of the C2-C20 fluorinated organic acid phase having a reduced content ratio of the fluorine-free organic compound compared with said mixture.