Naftifine hydrochloride is prepared by the reaction of (E)-N-methylcinnamylamine and 1-Chloromethylnaphthalene. The steps are as follows:
Step 1: (E)-N-methylcinnamylamine; 1-Chloromethylnaphthalene With sodium hydroxide In toluene at 86℃; for 6h;
Step 2: With hydrogenchloride In water; toluene at 15 - 20℃; for 3.5h；
Step 3: Add toluene (75 mL) to the yellow oil of step 2 (trans-N-cinnamomethylamine crude)And 15% NaOH (9.8g),Warming up,Stir well,When the temperature rises to 86 ° C,1-Chloromethylnaphthalene (11.8 g,100.2mmol), dripping,The reaction was incubated at 86 ° C for 6 h.Medium controlled N-cinnamylmethylamine is less than 0.5%,Cool down to 30 ° C, add water (75mL) to the system,Stirring and standing, separating the organic phase,The organic phase was washed with water (75 mL).Allow to stand and separate the organic phase, Concentrated hydrochloric acid (7.0 g) was added to the organic phase in a 15 ° C ice water bath.Adjust the pH to about 2 and stir for 0.5 h.After stirring at 20 ° C for 3 h, the filter cake was filtered.The filter cake was rinsed with toluene (20 mL).Obtained a wet cake (reduced naftifine hydrochloride) 19.5g;The wet crude product obtained in step 3 (crude naftifine hydrochloride) was added to isopropyl alcohol (38.6 g).Warmed to 85 ° C, dissolved,Slowly cool after dissolving,The cooling rate is 10 °C / h,A small amount of solid precipitated at 35 ° C.Crystallization at this temperature for 2 h,Continue to cool down to 20 ° C,Insulation for 3h,filter,Get the wet cake,The filter cake was dried under vacuum at 45 ° C.Obtained 16.2g of finished naftifine hydrochloride,The purity of the finished naftifine hydrochloride was 99.4% (HPLC normalization method).The product yield was 68.0%.The product yield is the molar yield,The calculation is as follows:Product yield (%)={m/[(m0/M0)*M]}*100%Symbol Description: m is the mass of the finished product, g; m0 is the mass of cinnamyl alcohol, g; M is the molar mass of naftifine hydrochloride,g/mol; M0 is the molar mass of cinnamyl alcohol, g/mol.
