Reaction #6343

Reaction equation

6-[3-benzyloxy-2-(diethoxyphosphorylmethoxy)propoxyamino]-4-chloro-2,5-diformamidopyrimidine

→

title compound

Yield 75.0%

9-[3-Benzyloxy-2-(diethoxyphosphorylmethoxy)propoxy]-6-chloro-2-formamidopurine

Yield 75.0%

Solvents

diethoxymethyl acetate

Conditions

Workup

1. 1
   TemperatureAfter cooling to ambient temperature
2. 2
   Otherthe solvent was evaporated
3. 3
   workup.DISSOLUTIONthe residue dissolved in methanol (10 ml)
4. 4
   OtherAfter 15 minutes at ambient temperature the solution was evaporated to dryness
5. 5
   OtherThe residue obtained
6. 6
   Otherwas chromatographed on silica gel (dichloromethane/methanol, 98:2 as eluant)

Procedure

A solution of 6-[3-benzyloxy-2-(diethoxyphosphorylmethoxy)propoxyamino]-4-chloro-2,5-diformamidopyrimidine (760 mg, 1.4 mmol) in diethoxymethyl acetate (2 ml) was stirred and heated in an oil bath at 120° C. for 2 hours. After cooling to ambient temperature, the solvent was evaporated and the residue dissolved in methanol (10 ml) and 0.880 ammonia (1 ml). After 15 minutes at ambient temperature the solution was evaporated to dryness. The residue obtained was chromatographed on silica gel (dichloromethane/methanol, 98:2 as eluant) to give the title compound as a colourless oil (550 mg, 75%). IR: νmax (film), 3400, 3220, 3110, 2980, 2900, 1710, 1610, 1580, 1510, 1475, 1440, 1385, 1330, 1240, 1160, 1140, 1095, 1050, 1020, 980, 920, 820, 780, 740, 700 cm-1. 1H NMR: δH [(CD3)2SO] 1.20, 1.21 (6H, 2×t, P-(OCH2CH3)2), 3.6-3.75 (2 H, m, CHCH2), 3.8-4.15 (7H, m, CH2CHCH2, OCH2P, P-(OCH2CH3)2), 4.52 (2H, s, OCH2Ph), 4.45-4.65 (2H, m, N-OCH2), 7.25-7.40 (5H, m, Ph), 8.81 (1H, s, H-8), 9.37 (1H, br.s, NHCHO), 11.31 (1H, br.s, D2O exchangeable NHCHO). Found: C, 48.11; H, 5 37; N, 12.50%. C21H27N5O7PCl requires: C, 47.77; H, 5.16; N, 13.27%. m/z: C21H28N5O7PCl requires 528.1415; observed 528.1363 (M +H+).

Source