Yield:350988-62-4 70%

Reaction Conditions:

with trichlorophosphate in N,N-dimethyl-formamide at 20 - 80; for 5 h;Cooling with ice;

Steps:

1 Synthesis of intermediate 2:

1 mL of phosphorus oxychloride was added to N,N-dimethylformamide (DMF, 3 mL), and the reaction was performed in an ice bath for 1 hour to obtain Westmeier reagent. Then, 5 mmol of intermediate 1 was added to the Westmeier reagent, and the reaction at room temperature was changed to 80 °C for 4 hours after 30 minutes of reaction. After completion, the reaction system was diluted with water and adjusted to neutral pH, extracted with ethyl acetate for 5 times, the organic phase was backwashed once with saturated sodium bicarbonate solution, dried, and spin-dried to obtain a red oily liquid crude product as the middle Body 2, 70% yield.

References:

CN113773255,2021,A Location in patent:Paragraph 0016; 0036-0039; 0043