Sulfonium salt, method for producing the same, and photoacid generator
A sulfonium salt compound represented by the following general formula (I): where R 1 and R 2 each denote the same or a different alkyl group having 1 to 18 carbon atoms, R 3 and R 4 each denote the same or a different alkyl group having 1 to 10 carbon atoms, X − denotes a sulfonate anion or a carboxylate anion, and the substituents denoted by R 3 O and R 4 O are each located at an arbitrary position selected from the 2-position to the 8-position of the naphthyl group.
1. A sulfonium salt compound represented by the following general formula (I):
where R 1 and R 2 each denote a butyl group, R 3 and R 4 each denote the same or a different alkyl group having 1 to 10 carbon atoms, X − denotes a sulfonate anion represented by the following general formula (II):
R 5 —SO 3 − (II), where denotes a 2-oxobornyl group, and the substituents denoted by R 3 O and R 4 O are each located at an arbitrary position selected from the 2-position to the 8-position of the naphthyl group.
2. The sulfonium salt compound according to claim 1 , wherein
R 3 and R 4 are each the same or a different alkyl group having 1 to 8 carbon atoms.
3. A photoacid generator containing the sulfonium salt compound according to claim 1 .
4. A method for producing a sulfonium salt compound, comprising:
a step (a) of subjecting, to dehydration condensation, a sulfoxide compound represented by the following general formula (IV):
where R 1 and R 2 each denote a butyl group,
and a naphthalene compound represented by the following formula (V):
where R 3 and R 4 each denote the same or a different alkyl group having 1 to 10 carbon atoms, and the substituents denoted by R 3 O and R 4 O are each located at an arbitrary position selected from the 2-position to the 8-position of the naphthyl group; and
a step (b) of producing a sulfonium salt compound represented by the following general formula (I):
where R 1 and R 2 each denote the same constituent defined in the foregoing general formula (IV), R 3 and R 4 each denote the same constituent defined in the foregoing general formula (V), and X − is represented by the following general formula (II):
R 5 —SO 3 − (II), where R 5 denotes a 2-oxobornyl group,
by a reaction between a dehydrated condensate obtained by the dehydration condensation in the step (a) and a salt compound or acid compound represented by a general formula X − Y + , where X − denotes the same constituent defined in the foregoing general formula (II), and Y + denotes an alkali metal ion or a hydrogen ion.