Fig. 6.

¹⁵N NMR spectra of ¹⁵N-ethyl nicotinate showing hyperpolarized spectra acquired by ADAPT-SABRE method in seconds and (b) corresponding thermal spectra obtained by 90$°$ hard pulses over 400 transients with 120 s of recycle delays (total experimental time of 13.5 h). The free¹⁵N resonance peak was observed at 303.2 ppm whilst the ‘equatorial-bound’ peak was found at 255.6 ppm.