A Chain-Growth Mechanism Underlying the Formation of Aromatic Pentamers

2 A Chain-Growth Mechanism Underlying the Formation of Aromatic Pentamers 

As illustrated in Fig. 9.18, this section [60] will provide convincing evidences and detailed analysis that support a stepwise chain-growth mechanism underlying the preferred formation of live-residue aromatic pentamers by one pot macrocyclization 

Competition experiments for mechanistic elucidation. The data presented in Sect. 5.1 only provide very preliminary insights into chain growth mechanism underlying one-pot macrocyclization. To further confirm this hypothetical mechanism, a new set of competition experiment has to be and was designed that involves monomer 17b, dimer 17h, and trimer 17i in various ratios, affording reaction mixtures containing up to five circular pentamers 16a, 16b, 16j, 161 and 16m with their isolated chemical yields tabulated in Table 9.12 and TLC-mediated separation illustrated in Fig. 9.19. 

If one of the above coupling reactions involving K5 and K +i (n = 2-4) is significantiy much slower than all the others, a comparable yield for producing 16j and 161 is expected. Indeed, in the absence of other closely related competing 

Entry Reacting partners Product distribution patterns and yields (%)  

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