17O NMR studies of boronic acids and their derivatives

Influence of fluorine substituents on the NMR properties of phenylboronic acids

“…The paper presents a comprehensive NMR spectroscopic characterization ( 1 H, 11 B, 13 C, 19 F, and 17 O) of all fluoro‐substituted phenylboronic acids (Fig. ) and is a continuation of our previous NMR studies on boronic acids and its derivatives …”

Novel 2,6-disubstituted phenylboronic compounds – Synthesis, crystal structures, solution behaviour and reactivity

“…This is the result of steric interactions with a second eCHO substituent. As it has been shown in series of arylboronic acids, steric interactions are major parameter affecting the 17 O NMR chemical shifts of the eB(OH) 2 group [25]. Steric and electronic effects cause also the deshielding of aldehyde oxygen signal.…”

“…Equilibrium constant for this reaction can be easily determined by NMR method on the basis of the integration of the corresponding signals in 1 H NMR spectra [25]. The value of cyclization reaction equilibrium constant (K cycl ) for 1 is 1.05 ([ 2 H] 6 -acetone, 298 K, c ¼ 0.02 M).…”

17o NMR

“…In particular, the influence of the substituents present in the phenyl ring of phenylboronic acids and their derivatives on the 17 O chemical shift have been investigated. 151,152 The largest changes of 17 O shifts were observed for the ortho position. The effect of intermolecular hydrogen bond formation in the boronic acids also has been detected by 17 O chemical shift changes.…”