Orthodeuterium Induced 1H- and 2D-Hyperpolarization for MRI
Bargon J, Rizi R, Limbacher A
University of Bonn
Analagous to hyperpolarization derived from parhydrogen, strongly enhanced signals result from hydrogenations of appropriate substrates with orthodeuterium (o-D2). Although p-H2 is easier to enrich than o-D2, and the relaxation times of the deuterium nuclei (due to their quadrupole moment) are shorter, the T1 of the neighboring 1H nuclei or of other heteronuclei in the partially deuterated hyperpolarized product molecules are considerably longer, which renders this in situ technique attractive to generate 1H-, 13C-, or 15N-hyperpolarized contrast agents for MRI investigations. The enhancement factor for 1H in the hydrogenation with o-D2 of methyl propiolate using the catalyst [Rh(cod)(dppb)]BF4 is > 100.