Table 1.
Thiobenzoquinoid type ions in the spectra of derivatives of para-mercaptobenzoic acids.
| Compound | m/z (Rel. %) | Ion structure |
|---|---|---|
| 4-(Trifluoroacetylthio)benzoic acid | 125 (31) | HO+=C6H4=S |
| 4-(Pentafluoropropionylthio)benzoic acid | 125 (27) | |
| 4-(Heptafluorobutyrylthio)benzoic acid | 125 (24) | |
| 4-Methoxycarbonylthiobenzoic acid | 125 (58) | |
| 4-Ethoxycarbonylthiobenzoic c acid | 125 (20) | |
| 4-n-Propyloxycarbonylthiobenzoic acid | 125 (14) | |
| 4-Isopropyloxycarbonylthiobenzoic acid | 125 (13) | |
| Methyl 4-(methoxycarbonylthio)benzoate | 139 (31) | CH3O+=C6H4=S |
| Methyl 4-(ethoxycarbonylthio)benzoate | 139 (26) | |
| Methyl 4-(n-propyloxycarbonylthio)benzoate | 139 (26) | |
| Methyl 4-(isopropyloxycarbonylthio)benzoate | 139 (17) | |
| Methyl 4-(trifluoroacetylthio)benzoate | 139 (46) | |
| Methyl 4-(acetylthio)benzoate | 139 (13) | |
| Ethyl 4-(ethoxycarbonylthio)benzoate | 153 (9) | C2H5O+=C6H4=S |
| n-Propyl 4-(n-propyloxycarbonyl thio)benzoate | 167 (3) | C3H7O+=C6H4=S |
| Trifluoroacetyl 4-(trifluoroacetylthio)benzoyl anhydride | 193 (11) | CF3O+=C6H4=S |
| Trimethylsilyl 4-(trifluoroacetylthio)benzoate | 166 (12) | (CH3)2Si=C6H4=S+ |
| Trimethylsilyl 4-(pentafluoropropionylthio)benzoate | 166 (12) | |
| Trimethylsilyl 4-(heptafluorobutyrylthio)benzoate | 166 (14) | |
| t- Butyldimethylsilyl 4-(trifluoroacelylthio)benzoate | 166 (6) | |
| t-Butyldimethylsilyl 4-(pentafluoropropionylthio)benzoate | 166 (10) | |
| t-Butyldimethylsilyl 4-(heptafluorobutyrylthio)benzoate | 166 (11) | |
| Trimethylsilyl 4-(trimethylsilylthio)benzoate | 166 (12) | |