Sodium Iodide → HCID 20331740, compound

Participants

Reaction Steps

The 2(3-hydroxy-n-octyl)-3-pyrazolidinone (6) used in this and subsequent examples is prepared according to the General Synthetic Scheme (Ic) shown above and described in more detail in U.S. Pat. No. 3,873,566. A mixture of 3.85 g (18 mmoles) of pyrazolidinone alcohol 6 and 4.90 g (about 18 mmoles) of the N(tert-butyl)-7-bromo(chloro)heptanamide (Example 1a), 5.0g NaHCO3, and 0.25 g NaI in 25 ml of tetramethylene sulfone was heated at 70° for about 56 hrs. The mixture was cooled, poured into 300 ml of H2O and 5% NaOH was added to adjust the pH to 9. The mixture was extracted with ether twice. The combined ether extracts were washed with water and with saturated NaCl solution and dried over anhy. Na2SO4. The dry solution was filtered and treated with HCl gas until no more of the hydrochloride salt (8) separated (as a oil). The oil 8 was run into a separatory funnel, mixed with 50 ml of 5% Na2CO3 solution and extracted into ether. Evaporation of the ether after drying over Na2SO4 gave 3.01 g of N(tert-butyl)7[3-oxo-2(3-hydroxy-n-octyl)pyrazolidin-1-yl]heptanamide 7 which, according to TLC on silica gel (2:1 acetone-toluene; iodine; Rf 0.37) was about 95% pure. The pmr spectrum (CDCl3, TMS) agreed with the assigned structure (tert-butyl 1.33 ppm), as did the IR spectrum [λmax 3320, 3070 (weak, sharp), 1670-1650 (broad, strong) cm-1 ]. A portion of this sample was further purified by preparative scale HPLC (6% MeOH/EtOAc) and analyzed by HRMS:

Provenance & Evidence