A sulfonium salt consisting of a carboxylate anion having a hydroxy group and fluorine or trifluoromethyl at ?- or ?-position and a phenyldibenzothiophenium cation having a hydrocarbylcarbonyl or hydrocarbyloxycarbonyl group has a high decomposition efficiency and a high acid diffusion controlling ability upon exposure. A resist composition comprising the sulfonium salt offers a high sensitivity, reduced LWR and improved CDU independent of whether it is of positive or negative tone.

A sulfonium salt consisting of a carboxylate anion having a hydroxy group and fluorine or trifluoromethyl at ?- or ?-position and a phenyldibenzothiophenium cation having a hydrocarbylcarbonyl or hydrocarbyloxycarbonyl group has a high decomposition efficiency and a high acid diffusion controlling ability upon exposure. A resist composition comprising the sulfonium salt offers a high sensitivity, reduced LWR and improved CDU independent of whether it is of positive or negative tone.

Disclosed is a practical method for production of 3,3-difluoro-2-hydroxypropionic acid, which is important as pharmaceutical and agrichemical intermediates. The method includes forming a 4,4-difluoro-2,2-dichloro-3-oxobutanoic acid ester by reaction of a 4,4-difluoro-3-oxobutanoic acid ester with chlorine (Cl.sub.2), forming 3,3-difluoro-1,1-dichloro-2-propanone by reaction of the chlorination product with an acid, and then, reacting the degradation product with a basic aqueous solution.

Disclosed is a practical method for production of 3,3-difluoro-2-hydroxypropionic acid, which is important as pharmaceutical and agrichemical intermediates. The method includes forming a 4,4-difluoro-2,2-dichloro-3-oxobutanoic acid ester by reaction of a 4,4-difluoro-3-oxobutanoic acid ester with chlorine (Cl.sub.2), forming 3,3-difluoro-1,1-dichloro-2-propanone by reaction of the chlorination product with an acid, and then, reacting the degradation product with a basic aqueous solution.

Disclosed are halo substituted derivative compounds of sobetirome with improved pharmacological characteristics relative to sobetirome, pharmaceutical compositions that include those compounds and methods of treating diseases such as neurodegenerative disorders using those pharmaceutical compositions.

Disclosed are halo substituted derivative compounds of sobetirome with improved pharmacological characteristics relative to sobetirome, pharmaceutical compositions that include those compounds and methods of treating diseases such as neurodegenerative disorders using those pharmaceutical compositions.

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).

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):

##STR00003##

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):

##STR00003##