Polymer-Supported Reagents and 1H–19F NMR Couplings: The Synthesis of 2-Fluoroacetophenone

Abstract

We describe an experiment for the undergraduate organic laboratory curriculum in which 2-bromoacetophenone is converted to 2-fluoroacetophenone using a solid-phase nucleophilic fluorine source. The experiment introduces students to the utility of solid-phase reagents in organic synthesis, to NMR-active nuclei other than 1H without the requirement of a special NMR probe, and to the unique uses of fluorine in molecular design.

Determination of Phosphorus Content in Cola Drinks by 31P NMR Spectroscopy Using External Calibration and Standard Addition Approaches

“…For 31 P determination, several basic pulse sequences can be used: zg, zg30, which do not include 1 H decoupling, zgpg, zgpg30, including the power gated 1 H decoupling, and zgig using the inverse gated 1 H decoupling. Though only remote, dissociable protons are present, 1 H decoupling is still favored, as it makes peaks slightly narrower. The suggested measurement is the zgig inverse gated decoupling pulse sequence, which avoids the nuclear Overhauser effect.…”

“…NMR spectroscopy is usually introduced as a part of organic chemistry courses in its traditional role as a structure elucidation tool. − There are only a few examples highlighting the versatility of NMR in education. These are related to chemical kinetics, − determination of p K a values, , quantitative determination of substances in drugs , or food − and NMR relaxometry. − Hands-on experience for students with the application of NMR spectroscopy to the measurement of nuclei other than 1 H and 13 C, although not unprecedented, ,,,− is especially scarce.…”

“…NMR spectroscopy is usually introduced as a part of organic chemistry courses in its traditional role as a structure elucidation tool. − There are only a few examples highlighting the versatility of NMR in education. These are related to chemical kinetics, − determination of p K a values, , quantitative determination of substances in drugs , or food − and NMR relaxometry. − Hands-on experience for students with the application of NMR spectroscopy to the measurement of nuclei other than 1 H and 13 C, although not unprecedented, ,,,− is especially scarce. In our teaching, we focus on the example of the 31 P nucleus, which is of special importance in organic catalysis as well as in biochemistry. − Due to its advantageous spectroscopic properties (Table S5), it is easily measurable, an important feature when considering the length of a laboratory practical.…”