Figure 3.

Diagram of the para-hydrogen-induced hyperpolarization side-arm hydrogenation (PHIP-SAH) procedure. (1) Functionalization of the carboxylate group with the side-arm; (2) para-hydrogenation of the unsaturated alcohol; (3) transfer of para-hydrogen spin order to the ¹³C spin of the carboxylate group; (4) cleavage of the side-arm. The yellow background indicates reaction steps taking place in the organic phase, while the blue background indicates that the molecule is dissolved in the aqueous phase. This figure was adopted according to Reference [98].