98 results about "Wittig reaction" patented technology

The invention discloses synthesis and antitumor activity research of a novel drug small molecular formula (1) containing a phenothiazine structure. R is # imgabs 1 #. 10H phenothiazine is used as an initial raw material, (E)-3-(10-ethyl-10H-phenothiazin-3-yl) acrylic acid is generated through a typical Friedel-Crafts alkylation reaction, an NBS bromination reaction and the like, and then an important intermediate compound 6 is synthesized through a Wittig reaction and a hydrolysis reaction. And carrying out coupling reaction on the intermediate compound 7 and different amine compounds to obtain 11 target compounds 7a-7k: formula (1). A CCK-8 experiment is carried out on a target compound to obtain a conclusion that the target compound 7a-7k and 5-fluorouracil are tested at the concentration of 20 mu M, and the result shows that the compound 7f has the best inhibition effect on A549, Hep G2 and HeLa cells, and the compound 7c has the better inhibition effect on the A549 cells. IC50 value calculation is carried out on a target compound under various concentrations, the IC50 value of 7c to HELA cells is small, the IC50 value of 7f to Hep G2 and HeLa cells is minimum, and the inhibition effect is the best. Therefore, the compound can be used for antitumor drugs.

The present invention discloses a synthesis method of ursodeoxycholic acid by using the plant-derived compound BA as a raw material to synthesize ursodeoxycholic acid through the steps of ethylene glycol or neopentyl glycol protection, oxidation, Wittig reaction, deprotection, reduction and hydrolysis, etc. The raw materials used for the synthesis of ursodeoxycholic acid in the present invention are cheap and easy to get, the synthesis steps are easy to operate, the yield is high, the reaction is environmentally friendly, and the industrial production is convenient.

The invention belongs to the technical field of organic synthesis, and particularly discloses a method for preparing megastigmatrienone, and the method for preparing megastigmatrienone comprises the following steps: taking 5-bromo-1, 3-pentadiene as an initial raw material, and reacting with trivalent phosphine to prepare phosphine salt; carrying out alkali treatment to obtain a Wittig reagent, and carrying out Wittig reaction on the Wittig reagent and acetyl vinyl acetate to obtain acetate-substituted conjugated tetraene; under the co-catalysis of copper and a large-steric-hindrance ligand, carrying out a Diels-Alder reaction with isobutene to construct a six-membered ring; hydrolyzing to obtain alcohol, and oxidizing to obtain ketone; under the acidic condition, conjugated diene at the tail end is subjected to rearrangement isomerization, and megastigmatrienone is obtained; the raw materials and reagents are simple, cheap and easy to obtain, the reaction steps are short, the yield is high, separation is easy, and the method is suitable for large-scale production.

Disclosed in the present invention is a method for synthesizing high-purity plant-derived cholesterol. By taking plant-derived 21-hydroxy-20-methylpregn-4-en-3-one, also called bisnoralcohol or BA, as a raw material, cholesterol is synthesized by means of steps such as oxidation, Wittig reaction, acetylation, reduction and selective hydrogenation reduction, or the cholesterol is synthesized by means of steps such as oxidation, Wittig reaction, acetylation, reduction, hydroxyl protection, selective hydrogenation reduction, deprotection or hydrolysis, and the purity can reach 99% or above. For the defect that there is cholesterol in a conventional animal source, according to the present invention, a plant-derived raw material, namely BA is used for synthesizing the cholesterol, such that the safety is high, the risk of pathogenic bacteria and virus infection is avoided, the synthesis yield is high, the product purity is good, the environment is friendly, and industrial production is facilitated; moreover, the present invention greatly reduces the impurity level in the product, facilitates the obtaining of high-purity cholesterol, and improves the safety of clinical use.

The invention relates to the field of chemistry or medicinal chemistry, in particular to a synthesis method of isoxazoline anti-parasitic drug lotirasodium. The synthesis method comprises the following steps: firstly, synthesizing an intermediate 1 (1, 2, 3-trichloro-5-(1-trifluoromethyl-vinyl) benzene); then synthesizing an intermediate 2 (5-bromo-4-methyl-2-thiophenecarboxime); the preparation method comprises the following steps: carrying out a 1, 3 dipolar cycloaddition reaction on an intermediate 1 and an intermediate 2 in sequence to obtain an intermediate 3, carrying out a Grignard reaction to obtain racemic acid, and finally carrying out chemical resolution and amide condensation in sequence to obtain lotirasodium. According to the novel synthesis method of the isoxazoline anti-parasitic drug lotirazine, wittig reaction is adopted for the first time to obtain the intermediate 1, operation is simpler and more convenient, and reaction conditions are mild. Besides, the synthesis method of the intermediate 2 is improved, so that the reaction conditions are milder, the operation is simpler, the cost is greatly reduced on the basis of reported reaction conditions, and the method is suitable for industrialization.

The present invention relates to the technical field of chemical synthesis, and in particular to a method for preparing a symmetrical double-terminal piperidinyl alkane, wherein the preparation method comprises the following steps: under the protection of an inert gas, a double-terminal halogenated alkane reacts with triphenylphosphine to prepare a phosphonium salt, namely an intermediate A, and then the intermediate A reacts with a piperidinone derivative under alkaline conditions to produce an intermediate B by Wittig reaction; the intermediate B is subjected to hydrogenation reduction to obtain the symmetrical double-terminal piperidinyl alkane; the raw materials of the preparation method of the present invention are easily available, the yield is high, and the preparation method is conducive to industrial production. The purity of the symmetrical double-terminal piperidinyl alkane obtained by the preparation method of the present invention is greater than 99%, and the total yield is 75-80%; the yield and purity are relatively high.

The application discloses a preparation method of beta-carotene, which comprises the following steps: 3-methyl-5-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2,4-pentadienyl triphenyl phosphonium salt (C15 phosphonium salt) cis-trans isomer and 2,7-dimethyl-2,4,6-octatriene-1,8-dial (C10) are dissolved in a water and a water incompatible solvent system, and Wittig reaction is generated under the action of an alkali. The reaction system can avoid that by-product inorganic salt is wrapped in the product, and the content of inorganic salt impurities in the product is reduced. In addition, the proportion of C15 phosphonium salt cis-trans isomer is controlled, a C15 phosphonium salt hydrolysis side reaction is inhibited, and the reaction yield is improved.

The invention relates to the technical field of chemical synthesis, and particularly discloses a compound with a peculiar smell removing function as well as a preparation method and application thereof. The chemical name of the compound is 2-ethoxy-3-((E)-methoxy-3-oxopropyl-1-alkene-1-yl) phenyl cinnamate, the smell of the compound is extremely light, sulfur-containing and nitrogen-containing compounds causing stink can be captured through a Michael addition reaction, and efficient peculiar smell removal is achieved. The preparation method comprises the following steps: (1) taking cinnamic acid as an initial raw material, and reacting with diethylamino sulfur trifluoride to prepare cinnamic acid acyl fluoride; (2) carrying out an esterification reaction on the cinnamic acid acyl fluoride and 2-methoxy-3-hydroxybenzaldehyde in the presence of 4-dimethylaminopyridine, so as to obtain 2-methoxy-3-formyl phenyl cinnamate; and (3) carrying out Wittig reaction on the 2-methoxy-3-formyl phenyl cinnamate and a phosphorus ylide reagent, so as to obtain the target compound.

The invention discloses a preparation method of beta-carotene. The preparation method comprises the following steps: dissolving an aqueous solution of 3-methyl-5-(2, 6, 6-trimethyl-1-cyclohexene-1-yl)-2, 4-pentadienyl triphenylphosphine salt (C15 phosphine salt) and 2, 7-dimethyl-2, 4, 6-octtriene-1, 8-dialdehyde (C10) cis-trans isomer in a solvent, carrying out wittig reaction under the action of alkali, and carrying out isomerization to obtain the product. By controlling the proportion of C10 cis-trans isomers of the reaction system, the content of the C25 aldehyde intermediate can be reduced, and the reaction yield and the product quality can be improved.

The invention discloses a preparation method of beta-carotene, which comprises the following steps: dissolving 3-methyl-5-(2, 6, 6-trimethyl-1-cyclohexene-1-yl)-2, 4-pentadienyl triphenylphosphine salt (C15 phosphine salt) cis-trans isomer and 2, 7-dimethyl-2, 4, 6-octtriene-1, 8-dialdehyde (C10) in water and a solvent system incompatible with the water, and carrying out wittig reaction under the action of alkali. The reaction system can prevent the byproduct inorganic salt from being wrapped in the product and reduce the content of inorganic salt impurities in the product. In addition, the proportion of cis-trans isomers of the C15 phosphonium salt is controlled, the hydrolysis side reaction of the C15 phosphonium salt is inhibited, and the reaction yield is increased.

The invention discloses THK01 and derivatives thereof, a preparation method and application of THK01 and derivatives thereof in preparation of anti-inflammatory drugs, and the THK01 and derivatives thereof are prepared by performing a series of chemical reactions on o-nitrobenzaldehyde containing a specific substituent group, including Wittig reaction, Diels-Alder reaction, Cadolan reaction, Fischer indole synthesis reaction, demethylation reaction, reduction reaction, click chemical reaction and the like. The THK01 structure modified derivatives with different substituent groups are obtained. The THK01 structure modified derivative disclosed by the invention is diversified in synthetic route and high in reaction success rate; in-vitro and in-vivo experiments show that the compounds can significantly inhibit NO generation and inflammatory response at low concentration, and can effectively treat inflammatory bowel disease and acute pneumonia induced by H1N1 virus in an animal model. These findings provide valuable candidate compounds and new treatment strategies for developing novel, safe and efficient anti-inflammatory drugs.

The invention relates to the technical field of organic synthesis, and provides a preparation method of 3-methoxy-4, 5-methylenedioxy phenylethylamine. According to the invention, myristic aldehyde and diethyl cyano phosphate are adopted as initial raw materials, and the 3-methoxy-4, 5-methylenedioxy phenylethylamine is prepared through wittig reaction, reduction reaction, hydrolysis reaction and Hofmann reaction. According to the preparation method provided by the invention, each step is simple and convenient to operate, the product yield is high (the total yield is 78.3%-84.2%), and the purity is high; furthermore, the preparation method provided by the invention is mild in reaction condition, does not need explosive and highly toxic chemicals, does not need column chromatography purification of products in each step, and is suitable for industrial production.

The invention relates to a preparation method of 3-butyl nonanol, which comprises the following steps: carrying out redox reaction on 2-butyl-1-octanol, NaDCC, a catalyst, a pH (Potential of Hydrogen) regulator and dichloromethane to prepare 2-butyl-1-octanal; the preparation method comprises the following steps: under the condition of protective gas, carrying out Wittig reaction on 2-butyl-1-octanal, PPh3CH3Br and K2CO3, so as to prepare 3-butyl-1-nonene; and carrying out a hydroboration-oxidation reaction on the 3-butyl-1-nonene, BH3. THF, H2O2 and NaOH, so as to prepare the 3-butyl nonanol. The preparation method is simple, convenient and mild in reaction condition.

The invention relates to a synthetic method of chlorinated methyl styrene, which comprises the following steps: (1) in the presence of a reducing agent, carrying out selective reduction reaction on terephthalaldehyde or isophthalaldehyde to obtain p-hydroxymethylbenzaldehyde or 3-(hydroxymethyl) benzaldehyde; (2) in the presence of a chlorination reagent, carrying out chlorination reaction on the p-hydroxymethylbenzaldehyde or 3-(hydroxymethyl) benzaldehyde obtained in the step (1) to obtain p-chloromethylbenzaldehyde or 3-(chloromethyl) benzaldehyde; and (3) in the presence of alkali, carrying out Wittig reaction on the p-chloromethyl benzaldehyde or 3-(chloromethyl) benzaldehyde obtained in the step (2) to generate p-chloromethyl styrene or m-chloromethyl styrene. The method avoids the use of highly toxic chlorine or intermediates difficult to synthesize, has the advantages of short steps, mild conditions, high selectivity, high yield, environmental friendliness and the like, and has a good industrial application prospect.

This invention provides a method for preparing high-purity olaparib, belonging to the field of pharmaceutical synthesis technology. The method uses dimethyl (3-oxo-1,3-dihydroisobenzofuran-1-yl)phosphate as the starting material, reacting it with compound 2 via a Wittig reaction to generate compound 3. Compound 3 reacts with hydrazine hydrate to generate compound 4. Compound 4 is hydrolyzed and acidified to give compound 5. Compound 5 reacts with thionyl chloride to give compound 6. Compound 6 is then condensed with compounds 7 and 9 to obtain olaparib. This invention uses readily available raw materials, is simple to operate and process, has mild reaction conditions, achieves a total yield of up to 90%, a purity >99%, is environmentally friendly, and is suitable for industrial production.

The present invention provides a method for preparing tretinoin. The Wittig reaction product of [3-methyl-5-(2,6,6-trimethylcyclohexen-1-yl)-2,4-pentadienyl]-triphenylphosphonium salt (Compound of Formula II) and 5-hydroxy-4-methyl-2-furanone (Compound of Formula III), namely the mixture of C11,13-dicis-tretinoin (Compound of Formula IV) and isotretinoin (Compound of Formula V), is subjected to two-step isomerization reactions: copper-catalyzed isomerization reaction (a) and iodine-catalyzed isomerization reaction (b) to prepare tretinoin by a one-pot method. This preparation method can avoid heavy metal pollution, has high selectivity, low cost, and the raw materials are easy to obtain or prepare, and is suitable for the industrial production of tretinoin.

The present invention relates to a pyridine derivative-containing triarylethylene photochromic material and its preparation and application methods. A pyridine ring or its derivative containing a formaldehyde substituent at one end is subjected to a Corey-Funchs reaction to synthesize its dibromosubstituted product; then, the dibromosubstituted product is reacted with an aromatic compound or heterocyclic compound containing a boric acid or pinacol borate group through a Suzuki reaction; or a benzophenone derivative is reacted with a pyridine ring or its derivative containing a diethyl phosphate group through a Wittig reaction to obtain the pyridine derivative-containing triarylethylene photochromic material. The present invention has low-cost raw materials and a simple and easy synthesis process. The prepared photochromic material has the advantages of dual light / proton response, high color purity, a wide color change wavelength range, and long color change durability. This expands the original triarylethylene photochromic material with a single stimulus response to a light / proton dual-responsive photochromic material, and also expands the color change range from orange to red and purple. The material is suitable for multiple fields such as inspection, storage encryption, and biological imaging.

The present invention provides a synthesis method for a 7-ketolithocholic acid or an intermediate thereof, which is prepared from a new intermediate I-1. According to the method, phytosterol degradation product bisnoralcohol is used as a starting material, and the 7-ketolithocholic acid or the intermediate thereof is obtained by means of an oxidation reaction, a Knoevenagel reaction (or wittig reaction), hydrogenation, a ketal protection reaction, an allylic oxidation reaction, ketal removal protection, and the hydrogenation. According to the method of the present invention, raw materials are easily available, the yield is high, reaction conditions are simple and mild, and the method is suitable for industrial production.

A method for the industrial production of teprenone and its application. The present invention belongs to the field of teprenone synthesis. The purpose of the present invention is to solve the technical problems of the existing teprenone synthesis method, which has a long route, many side reactions, and requires the use of special reagents. The method of the present invention comprises the following steps: first, farnesene is reacted with acetoacetate in the presence of a catalyst to obtain farnesene ketone ester, which is then decarboxylated to produce farnesene acetone, and then subjected to a reduction reaction, a halogenation reaction, and a Wittig reaction to obtain teprenone. The method avoids the shortcomings of existing processes, has fewer conversion steps in the synthesis route, and produces teprenone with high yield and purity, making it suitable for industrial production. The teprenone of the present invention is used as a drug for treating gastric diseases.

The invention relates to a preparation method of a cefditoren pivoxil intermediate. The preparation method comprises the following steps: step 1, adding GCLE, a bromine reagent and triphenylphosphine into an aprotic solvent for reaction to obtain a phosphorus ylide reagent; step 2, adding a mixed solvent and 4-methylthiazole-5-formaldehyde into the phosphorus ylide reagent, and carrying out Wittig reaction to obtain a cis-intermediate Z; 3, the cis-intermediate Z is added into phenol for a reaction; and adding immobilized penicillin acylase for reaction to obtain the cefditoren mother nucleus 7-ATCA. According to the synthesis process, generation of E-type impurities is reduced, and the purity of the product is improved.

The invention relates to a synthesis method of (S)-2, 2, 4-trimethyl pyrrolidine hydrochloride, which comprises the following steps: step a, carrying out Michael addition reaction on a compound 10 and a compound 11 in the presence of a solvent to prepare a compound 12; b, the compound 12 and ethyl bromoacetate are subjected to an affinity substitution reaction under the alkaline and solvent conditions, and a compound 13 is prepared; c, carrying out condensation ring closing reaction on the compound 13 under alkaline and solvent conditions to prepare a compound 14; step d, the compound 14 is subjected to a decarboxylation reaction under the acidic condition, and a compound 15 is prepared; e, the compound 15 is subjected to Wittig reaction under the alkaline condition, and a compound 16 is prepared; and step f, carrying out asymmetric hydrogenation reaction on the compound 16 to prepare a target compound 1, namely (S)-2, 2, 4-trimethylpyrrolidine hydrochloride. According to the synthetic method of the (S)-2, 2, 4-trimethylpyrrolidine hydrochloride, the reaction type of the whole synthetic route is safe, the yield of each step is relatively high, and industrial production is convenient to realize.

The application discloses a chemical synthesis method of 7-ketolithocholic acid (3alpha-hydroxy-7-keto-5beta-cholestane-24-oic acid), and belongs to the field of organic chemical synthesis. The 7-ketolithocholic acid is synthesized from a plant source compound BA through steps of glycol or neopentyl glycol protection, oxidation, Wittig reaction, deprotection, reduction and hydrolysis. The raw material used for synthesizing the 7-ketolithocholic acid is cheap and easy to obtain, the synthesis steps are simple and convenient to operate, the yield is high, the environment is friendly, and the industrialized production is facilitated.

The method comprises the following steps: taking androstane-3-ketone-4-ene-17beta-carboxylic acid shown in a formula II as a raw material, carrying out decarboxylation hydroxylation, sulfonylation, elimination and double-bond oxidative cracking to prepare the exemestane intermediate shown in a formula VI, and then sequentially carrying out allylic oxidation, wittig reaction and 1, 2, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3-trimethyl-1, 3, 4-trimethyl-1, 3 the exemestane shown in the formula I is prepared through the step of 1, 2-site dehydrogenation. The method has the characteristics of simple process operation, mild conditions, high reaction yield and the like, and is suitable for industrial production.

The invention discloses a synthesis method of 6-pentyl-2H-pyran-2-ketone, which comprises the following steps: step 1, reacting n-hexanoic acid or n-hexanoyl chloride with a malonate compound to obtain a compound a; step 2, carrying out carbonyl ketal protection reaction on the compound a to obtain a compound b; 3, the compound b is subjected to a reduction reaction, and a compound c is obtained; 4, the compound c is subjected to an oxidation reaction, and a compound d is obtained; 5, the compound d is subjected to a Wittig reaction, and a compound e is obtained; step 6, hydrolyzing the compound e, and removing a protecting group to obtain a compound f; and step 7, carrying out cyclization on the compound f, so as to obtain the 6-amyl-2H-pyran-2-one. According to the method, n-hexanoic acid (or n-hexanoyl chloride) serves as a starting raw material, 6PP is prepared through decarboxylation, ketal protection, reduction, oxidation, wittig reaction, hydrolysis deprotection and cyclization, the raw materials are cheap and easy to obtain, reaction conditions are mild, and the method is environmentally friendly and suitable for industrial production.

The application belongs to the technical field of pharmaceutical synthesis chemistry, and particularly relates to a preparation method of a small molecule Id protein inhibitor AGX51. The preparation method takes a piperonal compound 5 as a starting raw material, and obtains an olefin product compound 4 through a Wittig reaction. The compound 4 is subjected to double bond epoxidation and ring-opening reaction under alkaline conditions to synthesize a compound 3. The compound 3 is subjected to a Pinacol rearrangement reaction to obtain a compound 2. The compound 2 is subjected to Wittig olefination and hydrolysis reaction in series to obtain the compound 1. The compound 1 is subjected to reduction amination and acylation reaction in sequence to complete the synthesis of AGX51 in one pot. The structure of the target product is confirmed by MS, 1 H NMR and 13 C NMR. The structures of intermediates are confirmed by 1 H NMR. Through the preparation method, the total yield of the small molecule Id protein inhibitor AGX51 is significantly improved.

The present invention provides a method for synthesizing 7-ketolithocholic acid or its intermediates produced from a novel intermediate I-1. In the method, bisnoralcohol, a decomposition product of phytosterol, is used as a starting material, and 7-ketolithocholic acid or its intermediates can be obtained through oxidation, Knoevenagel reaction (or Wittig reaction), hydrogenation, esterification, ketal protection, allylic oxidation, ketal deprotection, and hydrogenation. The method of the present invention allows easy availability of raw materials, high yields, simple and mild reaction conditions, and is suitable for industrial production.

The invention provides an olefine aldehyde intermediate and a synthetic method thereof, and a synthetic method of conopomorpha sinensis sex pheromone, and belongs to the field of compound synthesis. According to the synthesis method of the olefine aldehyde intermediate, provided by the invention, 1, 5-pentanediol is taken as a raw material, and the high-yield olefine aldehyde intermediate is obtained through transesterification, first oxidation reaction, Wittig reaction and Sagsa oxidation reaction; the yield of the olefine aldehyde intermediate can be further improved by limiting a catalytic system and an auxiliary agent of the Sagsa oxidation reaction. Results of the embodiment show that the synthesis method provided by the invention does not adopt alkyne compounds, the yield of the product in the Sagassa oxidation reaction stage can reach 81%, the total yield of the obtained olefine aldehyde intermediate can reach 48.5%, the sex pheromone of conopomorpha sinensis prepared by adopting the olefine aldehyde intermediate can reach 39.8%, and the yield is high.

The invention discloses a method for synthesizing a key intermediate of pilocarpine. The invention provides a method for synthesizing a key intermediate of pilocarpine. The method uses 2,2-dimethyl-1,3-dioxane-5-one as a starting material, synthesizes 4-ethyl-5-oxy-2,5-dihydrofuran-3-acetic acid through Horner-Wadsworth-Emmons olefination, hydrolysis, oxidation, Wittig reaction, hydrolysis, oxidation and the like, and then synthesizes the final product according to the steps in the document "Concise Synthesis of Both Enantiomers of Pilocarpine".

The invention relates to a production process of (R, Z)-5-(1-decene) dihydrofuran-2 (3H)-ketone serving as a sex attractant of Japanese turtles, which comprises the following steps: (1) reacting 1-bromononane serving as a raw material with triphenylphosphine at a certain temperature and under the condition of a solvent to prepare nonyl triphenyl phosphorus bromide as shown in a formula (II); (2) taking 4-pentenoic acid as a raw material, and carrying out oxidation reaction and intramolecular esterification reaction in the presence of an oxidizing agent to prepare a target fragment (R)-5-hydroxymethyl dihydrofuran-2-one shown as a formula (III); (3) taking the (R)-5-hydroxymethyl dihydrofuran-2-ketone shown in the formula (III) as a raw material, and carrying out oxidation reaction to prepare a target fragment (R)-5-oxotetrahydrofuran-2-formaldehyde shown in the formula (IV); and (4) carrying out Wittig reaction on (R)-5-oxotetrahydrofuran-2-formaldehyde as shown in the formula (IV) and nonyltriphenylphosphorus bromide as shown in the formula (II) in the presence of alkali to prepare the (R, Z)-5-(1-decene) dihydrofuran-2 (3H)-ketone as shown in the formula (I). The method has the advantages of short reaction route, cheap and easily available raw materials, mild reaction conditions, easy amplification, small environmental pollution, and good economic and social values in popularization.

The invention relates to a total synthesis method of salvianolic acid F. The method comprises the following steps: brominating 2, 3-dimethoxybenzaldehyde to obtain 2-bromine-5, 6-dimethoxybenzaldehyde, carrying out Wittig reaction to obtain (E)-1-bromine-2-(3, 4-dimethoxystyryl)-3, 4-dimethoxybenzene, and carrying out reaction on (E)-1-bromine-2-(3, 4-dimethoxystyryl)-3, 4-dimethoxybenzene to obtain the salvianolic acid F. The preparation method comprises the following steps: taking salvianolic acid as a raw material, reacting with acrylate under the action of alkali and a palladium catalyst to obtain tetramethyl salvianolic acid F, and obtaining salvianolic acid F from the tetramethyl salvianolic acid F and a demethylation reagent. The preparation method is short in route and reasonable in process, the adopted reagent is safe, low in cost and free of environmental pollution, meanwhile, the preparation method has the advantages of simplicity in operation, easiness in separation and the like, and the obtained product is high in yield.