NMR Spectra of the Dimer and Trimer

The diastereomers of the dimer were identified through the splitting pattern observed for the methylene protons flanked by two methine protons the methylene protons of the r dyad are equivalent, while those of the m dyad are nonequivalent. 

The methine protons of the dimer and the trimer resonated in two chemical shift ranges. One occurred between 2.5-2.2 ppm, which is assigned to the m end and the mm center and the other between 2.2-2.0 ppm, which is assigned to the r end and the (rr + rm) center. It is noteworthy that the central methylene proton of 

The styrene dimer with propyl end groups has the end methyl (A), end methylene (B), external methylene (C), end me thine (D) and inner methylene carbons (E) in the main chain and the end phenyl group (i) as the side chain. The trimer has one new type of carbon atom, i.e., inner methine (D ), and the inner phenyl group (ii) along with the carbons and the phenyl group contained in the dimer. Furthermore, the tetramer possesses a central methylene carbon (F), and the pentamer possesses a central methine (D ) and a central phenyl group (iii). 

and 5 to the me thine carbons D and D . Resonances 2 and 3 were assigned to carbon D and resonace 5 to D by comparison with the other isomers and the dimer. 

Each isomer of the trimer has two or three types of phenyl C(l) carbons. The phenyl C(l) resonaces of the rr and mm isomers 

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