反应详情

A mixture of 11.5 gm of 1-(4-fluoro-phenyl)-piperazine 10.0 gm of 1,4-cyclohexanedione mono-ethylene ketal (available from Aldrich) and 27.2 gm NaB(OAc)3 in 250 ml dichloroethylene was kept for 18 hours at ambient temperature. The solvents were removed and the residue partitioned between ethyl acetate (200 ml) and 2N NaOH (200 ml). The ethyl acetate layer is washed with 2×20 ml water and dried over Na2SO4. The crude 1-(1,4-dioxa-spiro[4.5]dec-8-yl)-4-(4-fluoro-phenyl)-piperazine (20.1 gm of a solid) obtained after removing the solvents had a melting point of 116-118° C. A sample of this material (C18H25FN2O2) showed an elemental analysis of C, 67.24%, H, 8.22%. N, 8.98%.

1. customThe solvents were removed
2. customthe residue partitioned between ethyl acetate (200 ml) and 2N NaOH (200 ml)
3. washThe ethyl acetate layer is washed with 2×20 ml water
4. dry with materialdried over Na2SO4