3 results about "Hydrated chloral" patented technology

The invention relates to an L-proline heterocyclic intermediate, alpha-methyl-L-proline hydrochloride and a preparation method thereof, which comprises the following steps: step 01, cyclization upper protection: taking L-proline as a raw material, which is shown in a formula (1), to react with trichloracetic aldehyde hydrate under an acidic condition, and performing upper protection to obtain a heterocyclic intermediate as shown in a formula (2); the molar weight of chloral hydrate is 1-2.5 times of the molar weight of the L-proline shown in the formula (1), preferably 1.5 times of the molar weight of the L-proline shown in the formula (1). 02, methylation: reacting the heterocyclic intermediate as shown in the formula (2) obtained in the step 01 with lithium diisopropylamide, and after the reaction is completed, adding dimethyl sulfate for methylation to obtain an intermediate as shown in a formula (3); 03, deprotection: adding the intermediate as shown in the formula (3) obtained in the step 02 into a deprotection reagent for hydrolysis so as to obtain the alpha-methyl-L-proline hydrochloride as shown in the formula (4), so that the problems that the preparation cost of the existing alpha-methyl-L-proline hydrochloride is relatively high and the yield is relatively low can be solved.

The invention provides a preparation method of an indazole synthetic cannabinoid deuterated internal standard substance, and relates to the technical field of cannabinoid deuterated internal standard substances, and the preparation method comprises the following steps: 1, reacting aniline-D5 with chloral hydrate and hydroxylamine hydrochloride in a sodium sulfate aqueous solution to generate a compound 1; step 2, performing acid action on the compound 1 to generate a compound 2; 3, carrying out ring opening, diazotization, reduction and cyclization on the compound 2 to form a compound 3; 4, reacting the compound 3 with halogenated alkane under an alkaline condition to generate a compound 4; 5, the compound 4 and an amine compound are subjected to an amide condensation reaction, and the indazole synthetic cannabinoid deuterated internal standard substance is obtained. The raw materials are cheap and easy to obtain, and the preparation method is simple, so that the purpose of green and safe preparation of the indazole synthetic cannabinoid deuterated internal standard substance is achieved, and powerful support is provided for judicial expertise and drug banning work.

This invention relates to the field of indigo synthesis technology, specifically a method for synthesizing 6-chloro-7-fluoroindigo, including intermediate synthesis. 470 mL of water is added to a reaction flask, followed by the sequential addition of 5.5 mL of concentrated sulfuric acid, 28.64 g of hydroxylamine hydrochloride, 25 g of chloral hydrate, and 20 g of 3-chloro-2-fluoroaniline under stirring. After a white solid precipitates, 100-200 g of anhydrous sodium sulfate is added, and the mixture is heated to reflux for 1.5 hours. After monitoring the remaining raw material at less than 3% using online HPLC, the mixture is cooled to 0°C and filtered. The filter cake is recrystallized using an ethanol-water mixed solvent. The cyclization reaction utilizes a single or composite organic sulfonic acid catalyst, or a recyclable solid acid catalyst, to replace traditional concentrated sulfuric acid. This method has low equipment requirements, is equipped with temperature and pressure interlock devices for automatic cooling and pressure relief, and provides mild and safe reaction conditions, reducing safety risks. Through optimization of the catalyst system, reaction temperature, and time, the cyclization yield is increased from 25.4% to over 50%, significantly improving yield and production efficiency.