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Common methods for synthesizing adrenaline with a single enantiomer. This method includes using - Halogenated acetophenone serves as the starting material, and through amination and reduction reactions, a single enantiomer of adrenaline is ultimately obtained.

Step 1: Amination reaction

Firstly, the - Halogenated acetophenones react with amines to form corresponding amide compounds. This reaction is usually carried out under alkaline conditions, such as using sodium carbonate as a catalyst. A key step in the reaction mechanism is nucleophilic addition, forming an imide intermediate.

Chemical reaction formula: R-C6H4CH (Cl) C=O plus R'NH2 → R-C6H4CH (NHR ') C=O

Step 2: Reduction reaction

Next, a selective reducing agent is used to reduce the amide to generate the corresponding amino alcohol compound. Commonly used reducing agents include metal hydrides such as lithium aluminum hydride (LiAlH4) or sodium hydride (NaBH4). This reduction step causes the carbonyl group (C=O) in the amide to be reduced to hydroxyl group (- OH).

Chemical reaction formula: R-C6H4CH (NHR ') C=O plus 2 [H] → R-C6H4CH (NHR') CH2OH

Step 3: Chemical resolution

Chemical reaction formula (chiral separation): R-C6H4CH (NHR ') CH2OH → (R) - or (S) - adrenaline.

Step 1: Condensation reaction:

Firstly, catechins are reacted with chloroacetyl chloride or chloroacetic acid to form chloroacetyl protected catechol compounds. This condensation reaction is usually carried out under alkaline conditions, such as using triethylamine (Et3N) as a catalyst.

Chemical reaction formula: catechol plus ClCH2COCl → ClCH2C (OC6H4OH) 2

Step 2: Amination reaction:

Chemical reaction formula: ClCH2C (OC6H4OH) 2 plus R'NH2 → ClCH2C (OC6H4OH) 2NH-R '

Step 3: Reduction reaction:

Then, a selective reducing agent is used to reduce the amide to generate the corresponding amino alcohol compound. Commonly used reducing agents include metal hydrides, such as lithium aluminum hydride (LiAlH4) or sodium hydride (NaBH4). This reduction step causes the carbonyl group (C=O) in the amide to be reduced to hydroxyl group (- OH).

Chemical reaction formula: ClCH2C (OC6H4OH) 2NH-R ' plus 2 [H] → ClCH2C (OC6H4OH) 2CH2NH-R'

Step 4: Tartaric acid separation:

Chemical reaction formula (resolution): ClCH2C (OC6H4OH) 2CH2NH-R ' plus C4H6O6 → (R) - or (S) - adrenaline plus ClCH2C (OC6H4OH) 2CH2NH-R' (tartrate)

Compound a was obtained by using Xinfulin hydrochloride as the raw material and protected with boc groups under the action of an acid binding agent. Compound b was then oxidized by 2-iodobenzoic acid and reduced by sodium dithionite to obtain compound b. Compound b was then deprotected with boc protection groups by hydrochloric acid to obtain dl adrenaline like white powder. The specific steps are as follows:

Step 1: Preparation of Compound A

1. React Xinfulin hydrochloride with a binding agent to form Xinfulin binding salt.

2. Add a BOC-OSU condensation agent (such as N, N '- dipropylcarbodiimide) to react with a benzoate to generate a protected compound A.

Xinfu Linbing Salt plus BOC-OSU Condensing Agent → Compound A

Step 2: Preparation of Compound B

1. Oxidize compound A with 2-iodoylbenzoic acid to generate the corresponding acid.

2. Use reducing agents such as sodium hydrosulfite (Na2S2O4) to reduce the acid and obtain compound B.

Compound A plus 2-iodoylbenzoic acid → acid

Step 3: Prepare DL adrenaline

1. Use hydrochloric acid to remove BOC protection reaction from compound B and restore the natural hydroxyl group of adrenaline.

2. After appropriate subsequent treatment and crystallization purification, DL adrenaline like white powder was obtained.