14918-80-0

Usage

Synthesis

Vitamin A intermediated C5,namely 3- formylbut- 2- enyl acetate,which was used C15 + C5 synthesis route of vitamin A.?2- Chloro- 1- ethanol was used as starting material,esterified by acetic anhydride and protected by phosphate ester,and then reacted with 1,1- dimethoxy- 2propanone,trans- γ- acetoxytiglic aldehyde dimethyl acetal can be obtained,subsequently deprotection and 3- formylbut- 2- enyl acetate can be achieved.

Uses

3-Formylcrotyl Acetate can be used as a vitamin A intermediate.

InChI:InChI=1/C7H10O3/c1-6(5-8)3-4-10-7(2)9/h3,5H,4H2,1-2H3

Upstream product

• 38872-49-0 4-acetoxy-1-chloro-2-methyl-2-butene 
• 1515-76-0 1-acetoxybuta-1,3-diene 
• 201230-82-2 carbon monoxide 
• 1191-16-8 3-methylbut-2-enyl acetate 
• 10523-96-3 3-methyl-3-butenyl chloride 
• 3330-25-4 4-chloro-2-methyl-2-buteneal 
• 127-08-2 potassium acetate 
• 127-09-3 sodium acetate 
• 503-60-6 3,3-dimethyl-allyl chloride 
• 29773-17-9 4-acetoxy-2-methylen-butanal 
• 1576-98-3 1,4-diacetoxybut-2-ene 
• 1438-14-8 2-isopropyloxirane 
• 74549-14-7 (E/Z)-4-Acetoxy-2-methyl-2-butenal-dimethylacetal 
• 55311-87-0 E,Z-4-bromo-3-methyl-1-acetoxy-2-butene 

Downstream Products

• 127-47-9 Retinol acetate 
• 27231-36-3 5-methyl-1H-benzoimidazole-2-thiol 
• 1416548-67-8 4-hydroxy-3,7-dimethyl-9-(2,6,6-trimethylcyclohex-1-enyl)nona-2,7-dien-5-ynyl acetate 
• 51575-59-8 C₁₀H₁₈O₃ 
• 4172-46-7 2,6,11,15-tetramethyl-17-(2,6,6-trimethylcyclohex-1-enyl)heptadeca-2,4,6,8,10,12,14,16-octaenal 

Relevant academic research and scientific papers

Synthesis of analogues of citranaxanthin and their activity in free radical scavenging

Citranaxanthin and its analogues were synthesised via a C5 unit elongation to substituted conjugated polyenes. Their free radical scavenging activity was measured by 1,1-diphenyl-2-picrylhydrazinyl spectrophotometric methods. Results indicated that the new compounds exhibited antioxidant activities. Three new analogues had stronger antioxidant activity than citranaxanthin.

Process for preparation of 4-acetoxy-2-methyl-2-butene-1-aldehyde and intermediates thereof

The invention relates to the technical field of organic synthesis, and discloses a method for preparing 4-acetoxy-2-methyl-2-butene-1-aldehyde and an intermediate thereof. The method comprises the following steps: (1) in the presence of an esterification reagent, carrying out esterification reaction on 1, 4-butenediol to obtain 1, 4-butenediol diacetate; (2) in the optional presence of a first catalyst, carrying out an isomerization reaction on the 1, 4-butenediol diacetate to obtain 3, 4-diacetoxy-1-butene; (3) in the presence of a phosphorus-containing ligand and a rhodium catalyst and/or a cobalt catalyst, carrying out hydroformylation reaction on the 3, 4-diacetoxy-1-butene, carbon monoxide and hydrogen to obtain 2-methyl-3, 4-diacetoxy-1-butyraldehyde; (4) in the optional presence of a third catalyst, carrying out an elimination reaction on the 2-methyl-3, 4-diacetoxyl-1-butyraldehyde to obtain the 4-acetoxyl-2-methyl-2-butene-1-aldehyde. The method provided by the invention has the advantages of mild reaction conditions, environmental friendliness and high yield.

Preparation method of 4-acetoxy-2-methyl-2-butenal

The invention discloses a preparation method of 4-acetoxy-2-methyl-2-butenal, which takes salifying and wittig reactions as a core and methanol which is cheap and easy to obtain as a reaction initial raw material. The invention provides a new reaction route, the reaction steps are simple, the reaction conditions are mild, and the product yield is high.

Catalytic oxidation method for preparation of 4-acyloxy-2-methyl-2-butenal

The invention provides a preparation method of 4-acyloxy-2-methyl-2-butenal. The preparation method comprises the following steps: preparing raw materials, subjecting the raw materials prepared in thestep 1 to reacting, and carrying out after-treatment to obtain the 4-acyloxy-2-methyl-2-butenal. The preparation method of the 4-acyloxy-2-methyl-2-butenal is simple in process and mild in reaction conditions, and is carried out in the presence of a catalyst; the catalyst is good in catalytic activity, has excellent stability and durability, and can obtain a product with relatively high yield; and preparation cost is low, little waste salt and waste water are generated in the preparation process, the concept of green chemistry is accorded with, and industrial amplification feasibility is high.

Preparation method of 4-acetoxy-2-methyl-2-butenal

The invention discloses a method for preparing 4-acetoxyl-2-methyl-2-butenal, and the method comprises the following steps: forming a catalyst system by using a cobalt acid complex and a metal chloride, mixing 4-acetoxyl-2-methylene butyraldehyde (III) with hydrogen, and performing heating to react to obtain the 4-acetoxyl-2-methyl-2-butenal. In the prior art, precious metal needs to be used as a catalyst in the step, and the yield and the selectivity are not high. The method does not need to use a noble metal catalyst, is lower in cost, high in double-bond isomerization reaction speed and high in reaction yield, and is easy to realize industrial production.

Preparation method of chroma-stable 2 -methyl -4 - acetoxy -2 - butenal

The invention discloses a preparation method of a chromaticity-stable 2 -methyl -4 - acetoxy -2 - butenal, which comprises the following steps: (1) 2 - methylen -4 -acetoxybutyraldehyde and an auxiliary. Under the action of the catalyst, a gas - solid -liquid three-phase hydroisomerization reaction is generated to generate 2 - methyl -4 - acetoxy -2 - butenal. (2) The reaction was terminated after the reaction had been reached, the reaction was terminated and the solid phase catalyst was filtered off. (3) Distillation separation system solvent, hydrogenation by-product, unreacted starting material, obtained product 2 - methyl -4 - acetoxy -2 - butenal. The auxiliary agent in the step (1) is one or more organic compounds with amino and carbonyl functions, based on 2 - methylene -4 - acetoxybutyraldehyde of the raw material, 10 - 100 ppm, methacryloyloxy 2 - butanal provided by the invention is low in chroma, good -4 - in -2 - stability during long-term storage, slow in chroma and capable of meeting the downstream requirement better.

Preparation method of 4-acetoxy-2-methyl-2-butenal

The invention provides a preparation method of a vitamin A intermediate, namely 4-acetoxy-2-methyl-2-butenal. The method comprises the following steps: (1) carrying out ring opening on 3-methyl-1,2-epoxybutane under the action of alkaline acetate to generate 2-hydroxyl-3-butyl methyl acetate; (2) dehydrating 2-hydroxyl-3-butyl methyl acetate to obtain 3-methyl-2-butene acetate; and (3) carrying out one step selective oxidation on 3-methyl-2-butenyl acetate to obtain 4-acetoxy-2-methyl-2-butenal. According to the method, 3-methyl-1,2-epoxybutane is used as an initial raw material, the reactionsynthesis route is short, the atom economy is high, the operation is simple, and the method is an industrially optimized synthesis route.

Method for preparing 4-acetoxy-2-methyl-2-butenal

The invention provides a method for preparing 4-acetoxy-2-methyl-2-butenal. The method comprises the following steps: esterifying isopentenol to generate isopentenol acetate; and carrying out illumination oxidation on the isopentenol acetate in the presence of a photosensitizer to generate 4-acetoxy-2-methyl-2-butenal. The method has the advantages of cheap and easily available starting raw material isopentenol, high atom economy of the process route, no use of precious metals, less three wastes, and economic and effective synthesis route.

Low-cost preparation method of 2-methyl-4-substituted carbonyloxy-2-butenal

The invention provides a preparation method of 2-methyl-4-substituted carbonyloxy-2-butenal. The method comprises the following steps: carrying out a hydroformylation reaction on 1, 3-butadiene and synthesis gas (carbon monoxide and hydrogen) under the action of a catalyst to prepare 2-methyl-3-butenal, carrying out an addition reaction on the 2-methyl-3-butenal and halogen to prepare 2-methyl-3,4-dihalogenated butyraldehyde, and carrying out an elimination reaction and a substitution reaction on the 2-methyl-3, 4-dihalogenated butyraldehyde and carboxylate to prepare 2-methyl-4-substituted carbonyloxy-2-butenal. The method has the advantages of cheap and easily available raw materials, simple process flow, easy realization of reaction conditions, safe and simple operation, less wastewater generation amount, environmental protection, stable reaction intermediate product, appropriate reaction activity, high reaction selectivity, less side reactions, high target product yield and purityand low product cost, and is suitable for industrial production.

Preparation method of 2-methyl-4-acetoxy-2-butenal

The invention provides a preparation method of 2-methyl-4-acetoxy-2-butenal (I). The method comprises the steps: taking 2,2-disubstituent-4,7-dihydro-1,3-dioxepin (II) and synthesis gas as raw materials, performing hydroformylation reaction to prepare 2,2-disubstituent-5-formyl-4,7-dihydro-1,3-dioxepin (III), then performing reaction with an acetylation reagent to prepare 2-formyl-4-acetoxy-1-butene (IV), and performing double bond isomerization to obtain 2-methyl-4-acetoxy-2-butenal (I). The method has the advantages of cheap and accessible raw materials and low cost; the process flow is short, the reaction is easy to realize, the operation is safe, simple and convenient, the wastewater yield is low, and the green and environment-friendly effects are achieved; the method has the advantages of stable reaction intermediate product, proper reaction activity, high reaction selectivity, few side reactions and high yield, and is suitable for industrial production.