Radiation-sensitive resin composition, method for forming resist pattern and compound

A compound represented by formula (I):

• wherein, in the formula (I),
• Rx is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group;
• R1 and R2 each independently represent a substituted or unsubstituted chain aliphatic hydrocarbon group having 1 to 6 carbon atoms or a substituted or unsubstituted alicyclic hydrocarbon group having 3 to 6 carbon atoms, or R1 and R2 are bonded to each other to form a part of a 3- to 6-membered cyclic structure together with the carbon atom to which R1 and R2 are bonded;
• R3 represents a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms and comprising an alicyclic ring, wherein the alicyclic ring comprises —CF2— group, and the carbon atom of the —CF2— group is a ring atom of the alicyclic ring;
• provided that in R1 and R2, no fluorine atom is bonded to carbon atoms located at α-, β- and γ-positions of the carbon atom to which R1 and R2 are bonded;
• and
• in R3, no fluorine atom is bonded to carbon atoms located at α- and β-positions of the carbon atom to which R3 is bonded.

A compound represented by formula (i):

• wherein, in the formula (i),
• R1 and R2 each independently represent a substituted or unsubstituted chain aliphatic hydrocarbon group having 1 to 6 carbon atoms or a substituted or unsubstituted alicyclic hydrocarbon group having 3 to 6 carbon atoms, or R1 and R2 are bonded to each other to form a part of a 3- to 6-membered cyclic structure together with the carbon atom to which R1 and R2 are bonded;
• R3 represents a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms and comprising an alicyclic ring, wherein the alicyclic ring comprises —CF2— group, and the carbon atom of the —CF2— group is a ring atom of the alicyclic ring;
• provided that in R1 and R2, no fluorine atom is bonded to carbon atoms located at α-, β- and γ-positions of the carbon atom to which R1 and R2 are bonded;
• and
• in R3, no fluorine atom is bonded to carbon atoms located at α- and β-positions of the carbon atom to which R3 is bonded.