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52 Chapter 3
with that of the Ru II,III -BTC (Figure 3.19). The bands corresponding to the νs(COO) and
νas(COO) vibrations appear at 1359 cm -1 and 1429cm -1 , respectively, suggesting the
coordination of the carboxylate groups of framework BTC. However, presence of
unreacted acetic acid and H3BTC cannot be strictly excluded from IR, as the bands
stemming from C=O stretching in Ru-MOF samples is too small to be distinguished. The
1 H-NMR spectrum of acid-digest sample 5 displays peaks at 8.60 and 1.86 ppm (Figure
7.13). The former resonance is originated from the aromatic protons of BTC. However, the
latter one can be attributed to the protons of acetate, suggesting the presence of AcO(H)
in the obtained sample.
H 3
BTC
(C=O)
Ru II,II
2 (OOCCH 3 ) 4
5
Ru II, III -BTC
4000 3500 3000 2500 2000 1500 1000 500
wavenumber, cm -1
Figure 3.19. IR spectra of the Ru-BTC 5 in comparison with Ru II,III -BTC 1, [Ru 2 (OOCCH 3 ) 4 ] and
H 3 BTC. The vertical dash line corresponds to the position of ν(C=O) bands.