FIELD: organic chemistry, chemical technology, pharmacy. SUBSTANCE: invention relates to method of synthesis of ropivacaine hydrochloride monohydrate of the formula (I) 
that involves the following stages: 1 (i): racemic parent substance pipecoloxylidide hydrochloride of the formula (II) 
is cleared of HCl that forms salt with its by extraction with organic solvent containing diluted base; (ii): obtained pipecoloxylidide is treated with separating reagent and diluting agent forming the stable crystallizing system with water and crystalline product (S)-pipecoloxylidide of the formula (III) 
is isolated by extraction with diluted base in organic solvent that dissolves at least 1 wt.% of water; stage 2 (i): (S)-pipecoloxylidide of the formula (III) is alkylated with 1-halogenpropane in the presence of base and, optionally, in the presence of iodide catalyst at heating and then inorganic salts are removed by extraction with water; (ii): solution obtained at the stage 2 (i), if necessary, is diluted, precipitated with hydrochloric acid as ropivacaine hydrochloride of the formula (IV) 
followed by its isolation; stage 3: product obtained at the stage 2 (ii) is dissolved in an aqueous acetone, product of the formula (I) is precipitated by acetone addition and this product is isolated and dried. Proposed method ensures to obtain compound of the formula (I) showing topical anesthetic activity. EFFECT: improved method of synthesis, increased yield, high purity degree. 19 cl, 2 tbl, 3 ex
