21934-70-3

Usage

Uses

Used in Biological Research:
3',6'-diethoxyfluorescein is used as a fluorescent probe for monitoring and visualizing chemical or biological activities involving acidity fluctuations. Its pH-sensitive fluorescence enables researchers to track and measure changes in pH levels within biological systems.
Used in Optical Microscopy:
3',6'-diethoxyfluorescein is used as a fluorescent dye in various forms of optical microscopy, allowing researchers to visualize and study cellular structures and processes with enhanced clarity and detail.
Used in Chemical Research:
3',6'-diethoxyfluorescein is used as a spectroscopic tool in chemical research, providing insights into the interactions and properties of molecules within chemical systems. Its unique absorption and emission characteristics make it a valuable asset in the study of chemical reactions and processes.

Synthetic route

ethyl bromide (74-96-4) + fluorescein (2321-07-5) → 3',6'-Diethoxyfluorescein (21934-70-3)

Conditions	Yield
Stage #1: fluorescein With sodium hydroxide In N,N-dimethyl-formamide for 2h; Stage #2: ethyl bromide With sodium carbonate In N,N-dimethyl-formamide at 90℃; for 8h; Temperature;	80%

phthalic anhydride (85-44-9) + O-ethyl resorcinol (621-34-1) → 3',6'-Diethoxyfluorescein (21934-70-3)

Conditions	Yield
With zinc(II) chloride at 150 - 180℃;	15.2%

fluorescein (2321-07-5) → 3',6'-Diethoxyfluorescein (21934-70-3)

3.6-diethoxy-hydrofluoranoic acid → 3',6'-Diethoxyfluorescein (21934-70-3)

Conditions	Yield
With chromic acid; acetic acid

diethyl ether of fluoresceinphenylhydrazide → 3',6'-Diethoxyfluorescein (21934-70-3)

Conditions	Yield
With hydrogenchloride beim Behandeln unter Druck;

diethyl ether of fluoresceinanilide → 3',6'-Diethoxyfluorescein (21934-70-3) + fluorescein (2321-07-5)

Conditions	Yield
With hydrogenchloride; acetic acid at 160℃; unter Druck;

3',6'-Diethoxyfluorescein (21934-70-3) + zinc dust + alcoholic-alkaline solution → 3.6-diethoxy-hydrofluoranoic acid

Upstream product

• 2321-07-5 fluorescein 
• 74-96-4 ethyl bromide 
• 85-44-9 phthalic anhydride 
• 621-34-1 O-ethyl resorcinol 

Relevant academic research and scientific papers

Preparation method of 3, 6-diethoxy fluorane yellow thermal dye

The present invention relates to the field of heat-sensitive dyes, and particularly relates to a preparation method of a 3, 6-diethoxy fluorane yellow thermal dye. The method is as follows: (1) in a reaction vessel, adding fluorescein and a solvent, and dissolving with stirring at room temperature for 1 to 2 hours; (2) adding sodium hydroxide for reacting for 1 to 2 hours, and then adding sodium carbonate; wherein the molar ratio of sodium carbonate to sodium hydroxide to fluorescein is 2: 2: 1-4: 2: 1; (3) heating to 40-90 DEG C, at the time of 2 to 4 hours adding dibromoethane, wherein the molar ratio of dibromoethane to fluorescein is 3: 1 to 5: 1, and after the addition is complete, reacting for 6 to 16 hours at the temperature of 40-90 DEG C; (4) adding water to cool to room temperature, stirring, dispersing and precipitating for 8 to 10 hours, filtering and drying to obtain a crude product; and (5) recrystallizing the crude product with a mixed solvent of ethyl acetate and dimethyl carbonate to obtain the 3, 6-diethoxy fluorane yellow thermal dye. The method is simple in process and suitable for industrial mass production, and can be widely used in medical CT film production.