作者:Victor L. Rendina、Jason S. Kingsbury
DOI:10.1021/jo202214e
日期:2012.1.20
A new protocol for titrating nonstabilized diazoalkane solutions by quantitative 19F NMR is reported. An excess of 2-fluorobenzoic acid dissolved in CDCl3 is treated with the diazoalkane solution at a low temperature, immediately forming the corresponding 2-fluorobenzoate ester upon warming. A significant difference in the 19F chemical shift between the ester and acid is seen, allowing facile and accurate
报道了通过定量19 F NMR滴定不稳定的重氮烷溶液的新方案。用重氮烷溶液在低温下处理溶解在CDCl 3中的过量的2-氟苯甲酸,在加热后立即形成相应的2-氟苯甲酸酯。观察到酯和酸之间在19 F化学位移方面存在显着差异,从而可以轻松,准确地积分来确定滴度。该过程安全,快速,并且可以高精度指示活性重氮烷浓度。