In this work the unsaturated precursor molecule [1-13 C]acetylene dicarboxylate at a concentration of 50 mM in D2O was completely hydrogenated with parahydrogen (86% enriched) at 80°C and a pressure of 9.6 bar in a high-pressure NMR tube to produce [1-13 C]fumarate. D2O is used (rather than H2O) to extend the lifetime of the spin order. After reaction, the protons are hyperpolarized in a nonmagnetic 'singlet state' . In our experiment, the proton singlet order was transformed into hyperpolarized magnetization on the 1-13 C spin by subjecting the sample to a magnetic field cycle . Here, a 'constant adiabaticity' fieldcycling profile was used. The chemical reaction and magnetic field cycle profile are shown in Fig. .