tert-butyl 2-diethoxyphosphorylacetate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of anhydrous lithium chloride (1.9 g, 45 mmol) in MeCN (100 ml) was added tert-butyl 2-(diethoxyphosphoryl)acetate (7.6 g, 30 mmol) at room temperature. The mixture was stirred for 30 min. TEA (6.4 ml, 45 mmol) was added and the mixture was stirred for another 30 min. Ethyl 4-oxocyclohexanecarboxylate (5.1 g, 30 mmol) was added and the mixture was stirred overnight. The precipitate was filtered off and the filtrate was concentrated to afford brown oil, which was purified by silica gel column (PE:EtOAc=10:1) to afford product (5 g, 62%). the mixture was stirred for another 30 min the mixture was stirred overnight The precipitate was filtered off the filtrate was concentrated to afford brown oil, which was purified by silica gel column (PE:EtOAc=10:1)

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Sodium hydride (NaH, 60% suspension in mineral oil; 440 milligrams (mg), 11.0 millimoles (mmol)) was suspended in THF (20 milliliters (mL)), and the mixture was cooled to 0° C. t-Butyl diethylphosphonoacetate (2.57 mL; 11.0 mmol) was added over 2 minutes (min) The mixture was stirred at 0° C. for another 15 min, during which time the grey slurry turned clear within 5 min. 4-[1-(4-Trifluoromethoxyphenyl)-1H-[1,2,4]triazol-3-yl]-benzaldehyde (3.04 grams (g); 9.13 mmol) was suspended in THF (20 mL) and then added dropwise via cannula to the solution above. The mixture was then warmed to 25° C., poured into saturated (satd) aqueous (aq) ammonium chloride (NH4Cl; 200 mL), and extracted with 50% ethyl acetate (EtOAc)/hexanes (3×100 mL). The combined organic extracts were then dried over sodium sulfate (Na2SO4) and concentrated in vacuo. The yellow solid residue was dissolved in dichloromethane (CH2Cl2; 10 mL) and rapidly stirred as hexanes (100 mL) was added dropwise over 30 min. The light yellow crystals were collected on a Büchner funnel and dried in vacuo to afford the title compound ((2.93 g, 74%). The filtrate was concentrated in vacuo and purified by chromatography on silica gel (gradient elution with 15% to 40% to 80% EtOAc in hexanes) to afford additional product (0.215 g, 5%): mp 167-169° C.; 1H NMR (400 MHz, CDCl3) δ 8.58 (s, 1H), 8.20 (d, J=8.3 Hz, 2H), 7.80 (d, J=8.9 Hz, 2H), 7.63 (d, J=15.8 Hz, 1H), 7.62 (d, J=8.5 Hz, 2H), 7.39 (d, J=8.6 Hz, 2H), 6.44 (d, J=16.0 Hz, 1H), 1.54 (s, 9H); HRMS-ESI (m/z) [M]+ calcd for C22H20F3N3O3, 431.146. found, 431.1457. was added over 2 minutes (min) The mixture turned clear within 5 min added dropwise via cannula to the solution above The mixture was then warmed to 25° C. extracted with 50% ethyl acetate (EtOAc)/hexanes (3×100 mL) The combined organic extracts were then dried over sodium sulfate (Na2SO4) concentrated in vacuo The yellow solid residue was dissolved in dichloromethane (CH2Cl2; 10 mL) rapidly stirred as hexanes (100 mL) was added dropwise over 30 min The light yellow crystals were collected on a Büchner funnel dried in vacuo