Discovery of 35180-01-9

At the same time, in my other blogs, there are other synthetic methods of this type of compound, Chloromethyl isopropyl carbonate, and friends who are interested can also refer to it.

Reference of 35180-01-9, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 35180-01-9 name is Chloromethyl isopropyl carbonate, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

Diesterification reaction: Under a nitrogen atmosphere, 100 g Tenofovir (PMPA) And 300ml N-methylpyrrolidone (NMP), the control temperature at 25 ~ 30 , shaking 30min, To dissolve, and then add 106g triethylamine (TEA), 20 ~ 30 shaking 30min until uniform; The above mixture was warmed to 60 ~ 65 , and stirred, In 15 ~ 20min rapid dropping 266g chloromethyl isopropyl carbonate (CMIC) Then warmed to 75 ~ 80 , shaking reaction 60 ~ 70min, When TLC real-time monitoring of the basic reaction of the reaction material completely (3% or less), and monoester content of 15% or less, When the area of the main peak of the product is more than 80%, the double esterification reaction is complete; Then the reaction system first use water bath cooling 5min, After using ice-water bath in 10-15 min the reaction system rapidly reduced to 10-15 ;Extraction and Separation: To the reaction system in step (1) was added 600 ml of ethyl acetate (EA) Heated at 10 ~ 15 , stirred for 15min and filtered, each time with 200ml ethyl acetate (EA) washed the filter cake three times, And the filtrate and the resulting filtrate was combined, to which was added 400ml 10 ~ 15 distilled cold water, Full shock, extraction and separation, the separated aqueous phase was extracted with ethyl acetate twice, The resulting organic phase was combined with the EA layer, washed twice with 1000 ml of distilled water, 300g of sodium chloride was added into the obtained water washing solution twice, dissolved with stirring and cooled down to 10 to 15 C, And then extracted with 500ml of ethyl acetate once, the organic phase was extracted and combined, Washed with 900 to 1000 ml of saturated saline (300 g of sodium chloride dissolved in 850 ml of distilled water) Finally, the organic phase was added 400g anhydrous sodium sulfate 60min after drying filtration;Salt-forming reaction: to step (2) dried and filtered about 2000ml filtrate was added to the reaction vessel, Then 32g fumaric acid (FMA) was added and the temperature was raised to 40 C in a nitrogen atmosphere and the reaction was stirred until the solution became clear. (4) Preparation of tenofovir disoproxil fumarate crude product: Step (3) The reaction solution was concentrated under reduced pressure at 40 C, most of the solvent was distilled off until a large amount of crystals were precipitated, Then the concentrate was naturally cooled to room temperature, and then placed in a -5 C freezer was allowed to cool more than 2h, filtered, The resulting filter cake was washed with a small amount of ethyl acetate 2 to 3 times, pumping dry weighed about 130g, 40 under blast drying 2h, weighed to give 85g Tenofovir disoproxil fumarate crude product, The HPLC detector purity of 98% or more;Recrystallization: Under a nitrogen atmosphere, the reaction vessel was charged with step (4) 85 g crude Tenofovir disoproxil fumarate and 500 ml isopropanol (IPA) The nitrogen atmosphere was warmed to 55 C and stirred for 15 min to clarify the solution. If not, the filtrate should be filtered and the filtrate rapidly crystallized. After the resulting solution was left to cool to room temperature, Placed in a freezer at 4 frozen 2h above, so recrystallized, filtered, rinsed with cold isopropyl alcohol cake, Drained, to obtain white wet crystal 108g, at 40 blast drying 2h or 40 under reduced pressure drying 4h, 72 g of tenofovir disoproxil fumarate finished product was obtained. Tenofovir disoproxil fumarate obtained by the above method was tested by HPLC, Its purity is higher than 99.5%, monoester is less than 0.5%, the sum of other impurities is not more than 0.1%, with tenofovir, The total molar yield is about 35-40%.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, Chloromethyl isopropyl carbonate, and friends who are interested can also refer to it.

Reference:
Patent; Jiangsu Han Sitong Pharmaceutical Co., Ltd.; Wang Duoping; Wei Genghu; Shi Jiagui; Yang Yu; (7 pag.)CN107400145; (2017); A;,
Ester – Wikipedia,
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