... Chemistry. ... Chemical shifts (δ) are expressed in parts per million relative to internal tetramethylsilane; coupling constants (J) are in hertz. ... acetone was evaporated, 1 M HCl was added, and the solution was extracted with Et 2 O (3 × 20 cm 3 ). The combined organic layers were ...
[Brana, Miguel F; Garcia, M Luisa; Lopez, Berta; de Pascual-Teresa, Beatriz; Ramos, Ana; Pozuelo, Jose M; Dominguez, M Teresa Organic and biomolecular chemistry, 2004 , vol. 2, # 13 p. 1864 - 1871]