... The Journal of Organic ... and the residue was partitioned between water and Et 2 O. The aqueous phase was extracted with Et 2 O, and the combined organic extracts were ... 1496 cm −1 ; 1 H NMR (CDCl 3 , 500 MHz) δ 1.79−1.93 (br s, 1 H), 2.00−2.12 (m, 2 H), 2.50 (d, J = 2.2 Hz ...