The stereochemistry of the protonated forms of heterocyclic bases
Tóm tắt
The configurational and conformational ratios of protonated 2,4-dimethyl- and 1,2,4-trimethyl-1,2,3,4-tetrahydrobenzofuro[3,2-c]pyridines and their conjugate bases were studied by PMR spectroscopy. The trimethyl derivatives have a 1,4-trans configuration. The equilibrium concentrations of the epimeric salts in solution were determined. In the crystalline state the salts exist in the form of the energetically more favorable epimer, which in solution has a completely equatorial conformation.
Tài liệu tham khảo
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