A kind of preparation method of 2,6,11,15-tetramethyl-2,4,6,8,10,12,14-hexadecadendial

Abstract

The invention provides a preparing method of 2,6,11,15-tetramethyl 2,4,6,8,10,12,14 hexadecene heptaene dialdehyde. The preparing method comprises the first step of using 1,2-dihalogenated ethane as a raw material, making 1,2-dihalogenated ethane react with triethyl phosphite under the effect of a catalyst through Michaelis-Arbuzov to obtain tetraethyl ethylenebisphosphonate; the second step of making phosphonate react with pyruvic aldehyde dimethyl acetal under an alkali effect and through Horner-Wadsworth-Emmons to obtain 3-methyl-4,4-dimethoxy-2-butylene-1-diethyl phosphate; the third step of making 3-methyl-4,4-dimethoxy-2-butylene-1-diethyl phosphate directly react with 2,7-dimethyl-2,4,6-octatriene-1,8-dialdehyde through a 'one pot method' without separation to obtain 2,6,11,15-tetramethyl-2,4,6,8,10,12,14-hexadecene heptaene dialdol methanol; the fourth step of making the acetal compound be subjected to hydrolysis protection under an acid condition to obtain the target compound 2,6,11,15-tetramethyl 2,4,6,8,10,12,14 hexadecene heptaene dialdehyde. According to the 'one pot method' processing technology, the raw materials are easy to obtain, and the preparing method is simple and coherent, simple in operation, mild in condition, good in yield, less in three wastes, and is thus suitable for industrialized production.

Description

technical field

[0001] The invention relates to a preparation method of 2,6,11,15-tetramethyl-2,4,6,8,10,12,14-hexadecaheptacenedialdehyde, which belongs to the intermediate of carotenoids in organic chemistry body synthesis. Background technique

[0002] 2,6,11,15-Tetramethyl-2,4,6,8,10,12,14-Hexadecanedialdehyde (hereinafter referred to as "crocetin dialdehyde"), CAS No. 502-70 -5, its structural formula is as follows:

[0003]

[0004] It is an important intermediate in the synthesis of carotenoids, and has important applications in the synthesis of β-carotene, astaxanthin, lycopene, β-apo-8'-carotene aldehyde, etc. Carotenoids are widely used in industries such as medicine, food, cosmetics and feed, and their demand is increasing day by day. The research on the synthesis of its intermediate crocetin dialdehyde is particularly valuable.

[0005] At present, the synthesis methods of crocetin dialdehyde mainly include enol ether condensation method, sulfone compound s...

Examples

Embodiment 1

[0049] A. Preparation of tetraethyl ethylene diphosphate

[0050] Add 18.8 g (0.1 mol) dibromoethane, 49.8 g (0.3 mol) triethyl phosphite, and 0.5 g tetrabutylammonium iodide to a dry 500 ml three-necked flask, and heat at 150-160° C. for reflux reaction 4 -5 h, the gas phase followed the reaction. After cooling down to 100°C, the unreacted raw material was distilled off by water pump under reduced pressure; the residue was crude product, and 26.3 g of product (about 120-125°C / 1mmHg) was obtained by vacuum distillation with oil pump. Gas phase analysis showed that the product content was 97%. Yield 87%.

[0051] B. "One-pot" preparation of 2,6,11,15-tetramethyl-2,4,6,8, 10,12,14-hexadecadedial

[0052] Under the protection of nitrogen, 150 ml of toluene and 16.8 g (0.15 mol) of potassium tert-butoxide solid were successively added to a dry 500 ml three-necked flask, and stirred evenly, and 36.3 g (0.12 mol) of tetraethyl ethylene diphosphate was added dropwise. , 11.8 g (0....

Embodiment 2

[0054] A. Preparation of tetraethyl ethylene diphosphate

[0055] Add 18.8 g (0.1 mol) dibromoethane, 49.8 g (0.3 mol) triethyl phosphite and 0.5 g nickel iodide to a dry 500 ml three-necked flask, and heat at 150-160°C for 4-5 h at reflux , followed by gas phase reaction. After cooling down to 100°C, the unreacted raw material was distilled out under reduced pressure by the water pump; the residue was a crude product, and 23.0 g of the product (about 120-125°C / 1mmHg) was obtained by vacuum distillation with an oil pump. The gas phase analysis showed that the product content was 96%, Yield 76%.

[0056] B. "One-pot" preparation of 2,6,11,15-tetramethyl-2,4,6,8, 10,12,14-hexadecadedial

[0057] Under the protection of nitrogen, 150 ml of toluene and 10.2 g (0.15 mol) of sodium ethoxide solid were successively added to a dry 500 ml three-necked flask, and the mixture was stirred evenly, and 36.3 g (0.12 mol) of tetraethyl ethylene diphosphate, 11.8 g (0.1 mol) of acetone alde...

Embodiment 3

[0059] A. Preparation of tetraethyl ethylene diphosphate

[0060] Add 18.8 g (0.1 mol) dibromoethane, 49.8 g (0.3 mol) triethyl phosphite and 0.5 g sodium iodide to a dry 500 ml three-necked flask, and heat at 150-160°C for 4-5 h at reflux , followed by gas phase reaction. After cooling down to 100°C, the unreacted raw material was distilled out by water pump under reduced pressure; the residue was crude product, and 21.7g of product (about 120-125°C / 1mmHg) was obtained by vacuum distillation with oil pump. Gas phase analysis showed that the product content was 96%. Yield 72%.

[0061] B. "One-pot" preparation of 2,6,11,15-tetramethyl-2,4,6,8, 10,12,14-hexadecadedial

[0062] Under the protection of nitrogen, 150 ml of toluene, 8.1 g (0.15 mol) of sodium methoxide solid were successively added to a dry 500 ml three-necked flask, and the mixture was stirred evenly, and 36.3 g (0.12 mol) of tetraethyl ethylene diphosphate, 11.8 g (0.1mol) of acetone aldehyde dimethyl acetal a...

technical field

[0001] The invention relates to a preparation method of 2,6,11,15-tetramethyl-2,4,6,8,10,12,14-hexadecaheptacenedialdehyde, which belongs to the intermediate of carotenoids in organic chemistry body synthesis. Background technique

[0002] 2,6,11,15-Tetramethyl-2,4,6,8,10,12,14-Hexadecanedialdehyde (hereinafter referred to as "crocetin dialdehyde"), CAS No. 502-70 -5, its structural formula is as follows:

[0003]

[0004] It is an important intermediate in the synthesis of carotenoids, and has important applications in the synthesis of β-carotene, astaxanthin, lycopene, β-apo-8'-carotene aldehyde, etc. Carotenoids are widely used in industries such as medicine, food, cosmetics and feed, and their demand is increasing day by day. The research on the synthesis of its intermediate crocetin dialdehyde is particularly valuable.

[0005] At present, the synthesis methods of crocetin dialdehyde mainly include enol ether condensation method, sulfone compound s...

Examples

Embodiment 1

[0049] A. Preparation of tetraethyl ethylene diphosphate

[0050] Add 18.8 g (0.1 mol) dibromoethane, 49.8 g (0.3 mol) triethyl phosphite, and 0.5 g tetrabutylammonium iodide to a dry 500 ml three-necked flask, and heat at 150-160° C. for reflux reaction 4 -5 h, the gas phase followed the reaction. After cooling down to 100°C, the unreacted raw material was distilled off by water pump under reduced pressure; the residue was crude product, and 26.3 g of product (about 120-125°C / 1mmHg) was obtained by vacuum distillation with oil pump. Gas phase analysis showed that the product content was 97%. Yield 87%.

[0051] B. "One-pot" preparation of 2,6,11,15-tetramethyl-2,4,6,8, 10,12,14-hexadecadedial

[0052] Under the protection of nitrogen, 150 ml of toluene and 16.8 g (0.15 mol) of potassium tert-butoxide solid were successively added to a dry 500 ml three-necked flask, and stirred evenly, and 36.3 g (0.12 mol) of tetraethyl ethylene diphosphate was added dropwise. , 11.8 g (0....

Embodiment 2

[0054] A. Preparation of tetraethyl ethylene diphosphate

[0055] Add 18.8 g (0.1 mol) dibromoethane, 49.8 g (0.3 mol) triethyl phosphite and 0.5 g nickel iodide to a dry 500 ml three-necked flask, and heat at 150-160°C for 4-5 h at reflux , followed by gas phase reaction. After cooling down to 100°C, the unreacted raw material was distilled out under reduced pressure by the water pump; the residue was a crude product, and 23.0 g of the product (about 120-125°C / 1mmHg) was obtained by vacuum distillation with an oil pump. The gas phase analysis showed that the product content was 96%, Yield 76%.

[0056] B. "One-pot" preparation of 2,6,11,15-tetramethyl-2,4,6,8, 10,12,14-hexadecadedial

[0057] Under the protection of nitrogen, 150 ml of toluene and 10.2 g (0.15 mol) of sodium ethoxide solid were successively added to a dry 500 ml three-necked flask, and the mixture was stirred evenly, and 36.3 g (0.12 mol) of tetraethyl ethylene diphosphate, 11.8 g (0.1 mol) of acetone alde...

Embodiment 3

[0059] A. Preparation of tetraethyl ethylene diphosphate

[0060] Add 18.8 g (0.1 mol) dibromoethane, 49.8 g (0.3 mol) triethyl phosphite and 0.5 g sodium iodide to a dry 500 ml three-necked flask, and heat at 150-160°C for 4-5 h at reflux , followed by gas phase reaction. After cooling down to 100°C, the unreacted raw material was distilled out by water pump under reduced pressure; the residue was crude product, and 21.7g of product (about 120-125°C / 1mmHg) was obtained by vacuum distillation with oil pump. Gas phase analysis showed that the product content was 96%. Yield 72%.

[0061] B. "One-pot" preparation of 2,6,11,15-tetramethyl-2,4,6,8, 10,12,14-hexadecadedial

[0062] Under the protection of nitrogen, 150 ml of toluene, 8.1 g (0.15 mol) of sodium methoxide solid were successively added to a dry 500 ml three-necked flask, and the mixture was stirred evenly, and 36.3 g (0.12 mol) of tetraethyl ethylene diphosphate, 11.8 g (0.1mol) of acetone aldehyde dimethyl acetal a...

Images