N-(tert-Butoxycarbonyl)-2-phenylglycine

In solution at room temperature N-(tert-butoxycarbonyl)-2-phenylglycine, C₁₃H₁₇NO₄, shows the presence of two confomers, Z and E, in the ratio 1:3, as a result of restricted rotation about the N-CO bond. In the solid state, however, only the Z isomer was observed [HN-N-C2-O4 173.1 (4)°], with the N-CO bond showing considerable double-bond character [N-C2 1.357 (3) Å].

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