Examination of subsequent reaction products enhanced through parahydrogen-induced nuclear polarization (PHIP)
摘要:
Homogeneous hydrogenation with parahydrogen yields strong nuclear spin polarization in the H-1 NMR spectra of the reaction products. This polarization can be transferred to subsequent reaction products and detected by in situ H-1 MMR spectroscopy. As a typical example, the hydrogenation of 1-phenylpropyne with parahydrogen generates the spin-polarized molecule 1-phenylpropene. Upon bromination of this product, its polarization is transferred to the reaction product 1,a-dibromo-l-phenylpropane. As a second example, polarization was observed in the addition product of DBr to spin-polarized dimethyl maleate which is generated from dimethyl acetylenedicarboxylate by addition of parahydrogen. Copyright (C) 2000 John Wiley & Sons, Ltd.