¹³C–¹⁵N Coupling constants in a series of twisted amides: relationships with C(O)–N twist angles

Abstract

For a series of ¹⁵N-labelled amides 1a–e with increasing C(O)–N twist angles, the one-bond ¹³C–¹⁵N coupling constants decrease, whereas the two-bond ¹³C–¹⁵N coupling constants increase.

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