Ammonium Chloride → HCID 178495100, compound

Participants

Reaction Conditions

Reaction Steps

A solution of lithium diisopropylamide (1.75 ml, 1.5M in cyclohexane) was added dropwise, with stirring, to a solution of diethyl 3-methoxy-3(1-trityl-1,2,4-triazol-3-yl)propane phosphonate (0.65 g, prepared as described in Example 25) in dry tetrahydrofuran (15 ml), under nitrogen and with temperature maintained below -60° C. After a further twenty minutes, a solution of N-fluorobenzenesulphonimide (0.51 g) in tetrahydrofuran (15 ml) was added dropwise to the stirred reaction mixture at below -60° C. The mixture was stirred for a further two hours at -78° C., allowed to warm to room temperature and to stand overnight. It was then poured into saturated ammonium chloride solution and extracted with ethyl acetate. The extracts were washed with brine, dried over magnesium sulphate and evaporated under reduced pressure. The residue was chromatographed on silica, using dichloromethane-ethanol (49:1) as eluant, to give diethyl (1RS,3RS; 1RS,3SR)-1-fluoro-3-methoxy-3(1-trityl-1,2,4-triazol-3-yl)propane phosphonate (0.21 g) as an oily mixture of diastereoisomers in a ratio of 3:1 or 1:3. NMR (CDCl3): δ 1.3(6H,2t), 2.5-2.7(2H,m), 3.3(3H,2 xs), 4.2(4H,m), 4.6-4.8(2H,m), 7.1-7.3(15H,m), 8.0(1H,2 xs). M/S: M+ 537. The structures were confirmed by 19F and 13C NMR.

Provenance & Evidence