Resist composition, method of forming resist pattern, novel compound and method of producing the same, and acid generator

A compound represented by general formula (I) shown below:

• wherein X represents —O—, —S—, —O—R3— or —S—R4—, wherein each of R3 and R4 independently represents an alkylene group of 1 to 5 carbon atoms;
• R2 represents an alkyl group of 1 to 6 carbon atoms, an alkoxy group of 1 to 6 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, a halogen atom, a hydroxyalkyl group of 1 to 6 carbon atoms, a hydroxyl group or a cyano group;
• a represents an integer of 0 to 2;
• Q1 represents an alkylene group of 1 to 12 carbon atoms or a single bond;
• Y1 represents an alkylene group of 1 to 4 carbon atoms or a fluorinated alkylene group;
• and M+ represents an alkali metal ion.

A method of producing a compound (I) represented by general formula (I) shown below, comprising subjecting a compound (I-3) represented by general formula (I-3) shown below and a compound (I-4) represented by general formula (I-4) shown below to dehydration/condensation, to thereby obtain said compound (I):

• wherein X represents —O—, —S—, —O—R3— or —S—R4—, wherein each of R3 and R4 independently represents an alkylene group of 1 to 5 carbon atoms;
• R2 represents an alkyl group of 1 to 6 carbon atoms, an alkoxy group of 1 to 6 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, a halogen atom, a hydroxyalkyl group of 1 to 6 carbon atoms, a hydroxyl group or a cyano group;
• a represents an integer of 0 to 2;
• Q1 represents an alkylene group of 1 to 12 carbon atoms or a single bond;
• Y1 represents an alkylene group of 1 to 4 carbon atoms or a fluorinated alkylene group;
• and M+ represents an alkali metal ion.

A compound represented by general formula (b1-1) shown below:

• wherein X represents —O—, —S—, —O—R3— or —S—R4—, wherein each of R3 and R4 independently represents an alkylene group of 1 to 5 carbon atoms;
• R2 represents an alkyl group of 1 to 6 carbon atoms, an alkoxy group of 1 to 6 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, a halogen atom, a hydroxyalkyl group of 1 to 6 carbon atoms, a hydroxyl group or a cyano group;
• a represents an integer of 0 to 2;
• Q1 represents an alkylene group of 1 to 12 carbon atoms or a single bond;
• Y1 represents an alkylene group of 1 to 4 carbon atoms or a fluorinated alkylene group;
• and A+ represents an organic cation.