Variable temperature 1H and 29Si NMR of diastereomeric 1,3-dihydroxy-1,3-bis[(2-dimethylaminomethyl)phenyl]-1,3-divinyldisiloxanes

Variable temperature NMR experiments of diastereomeric 1,3-dihydroxy-1,3-bis[(2-dimethylaminomethyl)phenyl]-1,3-divinyldisiloxanes, meso-1 and rac-1 having intramolecular hydrogen bondings were carried out. As temperature increased, the 1H NMRs of hydroxy groups of 1 resulted in a low frequency and their 29Si NMRs were very slightly shifted to a low frequency. Interestingly, the 1H NMR of two benzylic protons was split more widely as temperature increased.