ortho-, meta-, para- The positions of substituents are indicated by numbers except that o- (ortho), m- (meta), and p- (para) may be used in place of
1,2-, 1,3-, and 1,4-, respectively (cf. Rule A-12.3), for benzene derivatives.
This HTML reproduction of Sections A, B and C of IUPAC "Blue Book" is as close as possible to the
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Copyright 1979 IUPAC.] If you need to cite these rules please quote this reference as their source.
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