(R)-4-(((9H-fluoren-9-yl)methoxy)carbonyl)-1,4-oxazepane-6-carboxylic acid

Computational details:

10000 confs. were generated using the universal force field (UFF), then filtered for duplicates using an RMS-threshold of 0.1 Å. The UFF conformers in a 10 kcal/mol (i.e. ~360) were relaxed using DFT level of theory, i.e., the ADF program, BP86 functional and the TZP basis set. IR and VCD spectra were calculated for the conformers in 5 kcal/mol, i.e. 149, conformers. Starting from the relative energies predicted with DFT, the Boltzmann factors have been optimised using a genetic algorithm (see DOI:10.1039/c9sc02866e for details).