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The monocyclic aliphatic hydrocarbon group is preferably a group in which one hydrogen atom is eliminated from a monocycloalkane. The monocycloalkane is preferably one having 3 to 6 carbon atoms, and specifically, examples thereof include cyclopentane and cyclohexane. 

The polycyclic aliphatic hydrocarbon group is preferably a group in which one hydrogen atom is eliminated from a polycycloalkane. The polycycloalkane is preferably one hav› ing 7 to 12 carbon atoms, and specifically, examples thereof include adamantane, norbornane, isobornane, tricyclode› cane, and tetracyclododecane. 

In the case where the cyclic hydrocarbon group represented by Ra’ 3 is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. 

This aromatic ring is not particularly limited so long as it is a cyclic conjugated system having ( 4n+2) it electrons, and it may be either monocyclic or polycyclic. The number of car› bon atoms of the aromatic ring is preferably 5 to 30, more preferably 5 to 20, still more preferably 6 to 15, and especially preferably 6 to 12. Specifically, examples of the aromatic ring include an aromatic hydrocarbon ring such as benzene, naph› thalene, anthracene, and phenanthrene; and an aromatic het- erocyclic ring in which some of the carbon atoms constituting the above-described aromatic hydrocarbon ring are substi› tuted with a hetero atom. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specifically, examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring. 

Specifically, examples of the aromatic hydrocarbon group in Ra’ $^{3 }$include a group in which one hydrogen atom is elimi- nated from the above-described aromatic hydrocarbon ring or aromatic heterocyclic ring (an aryl group or a heteroaryl group); a group in which one hydrogen atom is eliminated from an aromatic compound containing two or more aromatic rings (for example, biphenyl or fluorene); and a group in which one hydrogen atom of the above-described aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group (for example, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, and a 2-naphthylethyl group). The number of carbon atoms of the alkylene group bonded to the above-described aromatic hydrocarbon ring or aromatic heterocyclic ring is preferably 1 to 4, more preferably 1 to 2, and especially preferably 1. 

In the case where Ra’ 3 is bonded to either Rail or Ra’ 2 to form a ring, the cyclic group is preferably a 4-membered to 7-membered ring, and more preferably a 4-membered to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group. 

Tertiary Alkyl Ester Type Acid Dissociable Group: 

Among the above-described polar groups, examples of the acid dissociable group which protects a carboxy group include an acid dissociable group represented by the follow› ing general formula (al-r-2). It is to be noted that among the acid dissociable groups represented by the following formula (al-r-2), a group constituted of an alkyl group is hereinafter sometimes referred to as "tertiary alkyl ester type acid disso› ciable group" for the sake of convenience. 

[Chemical formula 21] 

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In the formula, each ofRa’ 4 to Ra’$^{6 }$represents a hydrocar› bon group, and Ra’s and Ra’ $^{6 }$may be bonded to each other to form a ring. 

Examples of the hydrocarbon group represented by Ra’ $^{4 }$to Ra’ $^{6 }$include the same hydrocarbon groups as those exempli› fied above for Ra’ 3 • 4 

Ra’ is preferably an alkyl group having 1 to 5 carbon atoms. In the case where Ra’s and Ra’ 6 are bonded to each other to form a ring, a group represented by the following general formula ( al-r2-1) is exemplified. On the other hand, in the case where Ra’$^{4 }$to Ra’$^{6 }$are not bonded to each other and are each an independent hydrocarbon group, a group repre› sented by the following general formula (al-r2-2) is exem› plified. 

[Chemical formula 22] 

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<img src='content_image/941022.jpg'>

In the formulae, Ra’$^{10 }$represents an alkyl group having 1 to 10 carbon atoms; Ra’ 11 represents a group for forming an aliphatic cyclic group together with the carbon atom to which Ra’$^{10 }$is bonded; and each of Rai1 2 to Ra,1 4 independently represents a hydrocarbon group. 

In the formula (al-r2-1), the alkyl group having 1 to 10 carbon atoms represented by Ra’ $^{10 }$is preferably the group exemplified as the linear or branched alkyl group represented by Ra’ $^{3 }$in the formula (al-r-1). In the formula (al-r-1), as the aliphatic cyclic group which Ra’ 11 forms together with the carbon atom to which Ra’$^{10 }$is bonded, the groups exemplified as the aliphatic hydrocarbon group represented by Ra’ $^{3 }$in the formula (al-r-1), which is either a monocyclic group or a polycyclic group, are preferable. 4 

In the formula (a0-r2-2), each ofRa,1$^{2 }$and Ra,1 is prefer› ably independently an alkyl group having 1 to 10 carbon atoms. The alkyl group is more preferably the group exem› plified as the linear or branched alkyl group represented by Ra’ 3 in the formula (al-r-1), still more preferably a linear alkyl group having 1 to 5 carbon atoms, and especially pref- erably a methyl group or an ethyl group. 3 

In the formula (a0-r2-2), Ra,1 is preferably the linear or branched alkyl group exemplified as the hydrocarbon group represented by Ra’ 3 in the formula (al-r-1), or an aliphatic hydrocarbon group which is either a monocyclic group or a polycyclic group. Of these, Ra,1 $^{3 }$is more preferably the group exemplified as the aliphatic hydrocarbon group represented by Ra’ 3 , which is either a monocyclic group or a polycyclic group. 

(al-r-2) 

(al-r2-1) 

(al-r2-2) 

