HCID 178460558, compound → HCID 178511570, compound

Participants

Reaction Steps

(±)-cis-Isopropyl [3-(t-butyloxyamino)cyclopentanyl]methylphosphinate (10) (2.1 g, 9.6 mmol) was dissolved in aqueous HCl (6M, 40 cm3) and the solution heated at reflux for 30 h. After cooling, the solution was evaporated to dryness under reduced pressure. The residue was dissolved in water (10 cm3) and applied to an ion exchange column (Dowex 50, H+ form). The column was eluted with water until the eluate was colourless and pH neutral and then eluted with aqueous pyridine (1M). Ninhydrin positive fractions were combined and evaporated to dryness under reduced pressure. Residual traces of pyridine were removed by repeatedly redissolving the compound in water (20 cm3) and re-evaporating (3 times). Recrystallisation from ethanol/acetone and drying gave the title compound (11) as an off white solid (1 g, 46%): 1H NMR (300 MHz, D2O) δ 1.27 (3H, d, J=12.9 Hz, PCH3), 1.56-2.27 (7H, m, C(1)—H, C(2)—H, C(2)—H′, C(4)—H, C(4)—H′, C(5)—H and C(5)—H), 3.59 (1H, m, C(3)—H), 13C NMR (75.46 MHz, D2O) 13.02 (PCH3, d, JPC=92.0 Hz), 23.9 (C(5)), 30.50 (C(4), d, 3JPC=7.5 Hz), 31.55 (C(2)), 37.20 (C(1), d, JPC=97.3 Hz), 52.29 (C(3), d, 3JPC=9.3 Hz), 31P NMR (121 MHz, D2O) δ 45.9, MS (CI, CH4) m/z 164 (38%) (MH+), 147 (30), 105 (100). (ESI) 164.0822 (MH+-C6H15NO2P requires 164.0840).

Provenance & Evidence