The present invention provides a method for preparing a chiral 4-aryl-β-amino acid derivative. The preparation method comprises hydrogenating an enamine compound having a structure as shown in Formula III in an organic solvent in the presence of a catalyst containing a transition metal and BIBOPs. The preparation method of the present invention uses a small amount of a selected asymmetric catalyst, and has a simple operation, mild reaction conditions, a high yield, a high stereoselectivity, and better industrial application and economic values.

The present invention provides a method for preparing a chiral 4-aryl-β-amino acid derivative. The preparation method comprises hydrogenating an enamine compound having a structure as shown in Formula III in an organic solvent in the presence of a catalyst containing a transition metal and BIBOPs. The preparation method of the present invention uses a small amount of a selected asymmetric catalyst, and has a simple operation, mild reaction conditions, a high yield, a high stereoselectivity, and better industrial application and economic values.

The present invention provides a method for preparing a chiral 4-aryl-β-amino acid derivative. The preparation method comprises hydrogenating an enamine compound having a structure as shown in Formula III in an organic solvent in the presence of a catalyst containing a transition metal and BIBOPs. The preparation method of the present invention uses a small amount of a selected asymmetric catalyst, and has a simple operation, mild reaction conditions, a high yield, a high stereoselectivity, and better industrial application and economic values.

Provided herein are improved processes for convening C7-amino-substituted tetracylines to C7-fluoro-substituted tetracyclines as well as intermediates produced by or used in these processes. In one embodiment, a thermal fluorination method is provided in which a suspension comprising a non-polar organic solvent and a C7-diazo-substituted tetracycline hexafluorophosphate, hexafluoarsenate or hexafluorosilicate salt, or a salt, solvate or combination thereof is healed to provide a C7-fluoro-substituted tetracyline, or salt, solvate or combination thereof. In another embodiment, a photolytic fluorination is provided in which a solution comprising an ionic liquid and a C-7diazo-substituted tetracyline tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate or hexafluorosilicate salt, or a salt, solvate or combination thereof is irradiated to provide a C7-fluoro-substituted tetracyline, or salt, solvate or combination thereof.

Provided herein are improved processes for convening C7-amino-substituted tetracylines to C7-fluoro-substituted tetracyclines as well as intermediates produced by or used in these processes. In one embodiment, a thermal fluorination method is provided in which a suspension comprising a non-polar organic solvent and a C7-diazo-substituted tetracycline hexafluorophosphate, hexafluoarsenate or hexafluorosilicate salt, or a salt, solvate or combination thereof is healed to provide a C7-fluoro-substituted tetracyline, or salt, solvate or combination thereof. In another embodiment, a photolytic fluorination is provided in which a solution comprising an ionic liquid and a C-7diazo-substituted tetracyline tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate or hexafluorosilicate salt, or a salt, solvate or combination thereof is irradiated to provide a C7-fluoro-substituted tetracyline, or salt, solvate or combination thereof.

Provided herein are improved processes for convening C7-amino-substituted tetracylines to C7-fluoro-substituted tetracyclines as well as intermediates produced by or used in these processes. In one embodiment, a thermal fluorination method is provided in which a suspension comprising a non-polar organic solvent and a C7-diazo-substituted tetracycline hexafluorophosphate, hexafluoarsenate or hexafluorosilicate salt, or a salt, solvate or combination thereof is healed to provide a C7-fluoro-substituted tetracyline, or salt, solvate or combination thereof. In another embodiment, a photolytic fluorination is provided in which a solution comprising an ionic liquid and a C-7diazo-substituted tetracyline tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate or hexafluorosilicate salt, or a salt, solvate or combination thereof is irradiated to provide a C7-fluoro-substituted tetracyline, or salt, solvate or combination thereof.

An object of the present invention is to provide a method for producing a fluorinated organic compound, whereby an iodosylbenzene derivative can be easily separated and recovered. The above object can be achieved by a method for producing a fluorinated organic compound, comprising step A of fluorinating an organic compound (1) by reaction with a fluorine source (3) in the presence of a hypervalent iodine aromatic ring compound (2a), or in the presence of an iodine aromatic ring compound (2b) and an oxidant (2bo); wherein the fluorine source (3) is a fluorine source (3a) represented by formula: MF.sub.n, wherein M is H, a metal of Group 1 of the periodic table, or a metal of Group 2 of the periodic table; and n is 1 or 2; and step B of separating the iodine aromatic ring compound from a reaction liquid after step A is started.

An object of the present invention is to provide a method for producing a fluorinated organic compound, whereby an iodosylbenzene derivative can be easily separated and recovered. The above object can be achieved by a method for producing a fluorinated organic compound, comprising step A of fluorinating an organic compound (1) by reaction with a fluorine source (3) in the presence of a hypervalent iodine aromatic ring compound (2a), or in the presence of an iodine aromatic ring compound (2b) and an oxidant (2bo); wherein the fluorine source (3) is a fluorine source (3a) represented by formula: MF.sub.n, wherein M is H, a metal of Group 1 of the periodic table, or a metal of Group 2 of the periodic table; and n is 1 or 2; and step B of separating the iodine aromatic ring compound from a reaction liquid after step A is started.

There is provided a novel optically active bisphosphinomethane useful as a ligand for an asymmetric catalyst, excellent in oxidation resistance in air, and easy in handling. There is also provided a transition metal complex using the optically active bisphosphinoraethane having excellent asymmetric catalytic ability as a ligand. The optically active bisphosphinomethane is represented by the general formula (1), and the transition metal complex has the optically active bisphosphinomethane as a ligand. ##STR00001##
(In the formula, R.sup.1 represents an adamantyl group; R.sup.2 represents a branched alkyl group having 3 or more carbon atoms; and * represents an asymmetric center on a phosphorus atom.)

There is provided a novel optically active bisphosphinomethane useful as a ligand for an asymmetric catalyst, excellent in oxidation resistance in air, and easy in handling. There is also provided a transition metal complex using the optically active bisphosphinoraethane having excellent asymmetric catalytic ability as a ligand. The optically active bisphosphinomethane is represented by the general formula (1), and the transition metal complex has the optically active bisphosphinomethane as a ligand. ##STR00001##
(In the formula, R.sup.1 represents an adamantyl group; R.sup.2 represents a branched alkyl group having 3 or more carbon atoms; and * represents an asymmetric center on a phosphorus atom.)