Chemical Properties
2,4,7,9-Tetramethyl-5-decyne-4,7-diol is white to pale yellow low melting mass
Uses
2,4,7,9-Tetramethyl-5-decyne-4,7-diol is an acetylene glycol derivative used in water-based coatings and has both antifoaming and surfactant properties. It is highly toxic and have been found in acrylic adhesives used for food packaging multilayers manufacturing.
Uses
2, 4, 7, 9-tetramethyldec-5-yne-4,7-diol may be used to dope poly[9,9-bis(6′-(diethanolamino)hexyl)-fluorene],that acts as an interfacial layer in a heterojunction solar cell.
General Description
2, 4, 7, 9-tetramethyldec-5-yne-4,7-diol is a well-known acrylic adhesive. It has amphiphilic characteristics. It is used a dopant in a heterojunction solar cell, it assists in the formation of a homogeneous interfacial layer over the photoactive layer. Doping results in decreasing the absorption of photons in the underneath photoactive layer, thereby in enhancing the photocurrent density.
Hazard
In vivo experiments have shown that 2,4,7,9-Tetramethyl-5-decyne-4,7-diol induced lethargy in a lethal dose inhalation study in rats; tremors and convulsions were induced in a feeding study in dogs. It is an irritant to human skin and eyes, as well as a neurotoxic hazard to the rest of the central nervous system.
Flammability and Explosibility
Non flammable
Synthesis
1. the concentrated alkali solution from Example 1 was dehydrated under reduced pressure to obtain 14 g of paste.
2. the paste was mixed with 10 g of the novel coordination catalyst, 100 g of methyl isobutyl ketone, 40 g of cyclohexane and 31 g of divinyl ether.
3. The mixture was placed in a 500 mL autoclave, the air was replaced with nitrogen and the temperature was controlled at 40~45°C.
4. Acetylene was introduced into the reaction system, keeping the system pressure not higher than 0.1 MPa. When 11.7 g of acetylene was introduced, the pressure of the system was kept for 10 minutes and did not decrease any further, and the reaction was stopped. At this time, the reaction time was 5.5 hours.
5. After cooling to room temperature, the reaction solution in the autoclave was transferred to a 500 mL beaker, 10 g of deionized water was added, and the system was stratified.
6. 26 g of concentrated lye solution containing the lower layer of lye was isolated and transferred to a 250 mL beaker.
7. The organic layer was neutralized with 20% phosphoric acid solution to pH 6-7, and the brine layer was separated to give 190g of organic phase.
8. The organic phase was transferred to a 250mL three-necked flask and 17g of the semi-finished ethynediol product of Example 1 was added.
9. 37 g of cyclohexane was distilled at atmospheric pressure followed by a reduced pressure distillation.
10. 1.5 g of low boiling point material was collected at 60 °C under vacuum at -0.098 MPa, 31 g of pre-fraction was collected at 60-90 °C, and 28 g of diethylene glycol divinyl ether was collected at 90-120 °C.
11. 120 g of ethynediol semi-finished product was obtained at 120-150 °C and 85.5 g of ethynediol product was collected at 150-155 °C.
12. The heating was stopped, cooled to room temperature and 2 g of high boiling point residue remained in the beaker.
13. The yield of acetylene diol (relative to acetylene) was calculated to be 84.1%.
14. 20 g of potassium hydroxide and 200 g of diethylene glycol divinyl ether were weighed in a 500 mL three-necked flask and the reaction was heated to 60° C. with stirring until the potassium hydroxide was completely dissolved.
15. Weigh the above-prepared complexation catalyst, mix it with 100g methyl isobutyl ketone and 50g cyclohexane, put it into a 500mL autoclave, and replace the air with nitrogen.
16. Control the temperature at 40-45°C, pass acetylene into the reaction system, keep the system pressure not higher than 0.1 MPa.
17. When 10.4 g of acetylene was passed, the pressure of the system was maintained for 10 minutes and did not decrease any further, and the reaction was stopped. At this point, the reaction time was 6 hours.
18. After cooling to room temperature, the reaction solution was transferred to a 500 mL beaker, 10 g of deionized water was added, and the system was stratified.
19. 23 g of concentrated alkaline solution containing the lower layer of oxime was isolated and transferred to a 250 mL beaker.
20. The organic layer was neutralized with 20% phosphoric acid solution to pH 6-7 and the brine layer was separated to give 185g of organic phase.
21. The organic phase was transferred to a 250mL three-necked flask, 46g of cyclohexane was added, and the cyclohexane was distilled out at atmospheric pressure, followed by distillation under reduced pressure.
22. 1 g of low boiling point material was collected at 60 °C, 18 g of pre-fraction was collected at 60-90 °C and 31 g of diethylene glycol divinyl ether was collected at 90-120 °C at a pressure of -0.098 MPa.
23. 17 g of ethynediol semi-finished product was obtained at 120-150 °C and 69 g of ethynediol product was collected at 150-155 °C.
24. The heating was stopped, cooled to room temperature and 3 g of high boiling point residue remained in the beaker.
25. The yield of ethynediol (relative to acetylene) was calculated to be 76.3%.
Toxics Screening Level
The Initial threshold Screening Level (ITSL) is 70μg/m3 based on annual averaging.
References
[1] Patent: CN107963960, 2018, A. Location in patent: Paragraph 0058; 0059
