2-methyl anthraquinone is a series of 2-alkyl substituted anthraquinone products. It is an important organic intermediate. It is also used to prepare photosensitive compounds, dyes, light screening resins, pharmaceutical and pesticide intermediates.
In the previous article, we introduced the application of 2-alkyl anthraquinone in dyes. In this article, we will submit other applications.
Application 1: in the papermaking process, 2-Methylanthraquinone is a very efficient additive. It can penetrate the interior of wood chips and be reduced to 2-Methylanthraquinone. It is unstable and easy to oxidize. In this redox cycle, the components in wood chips are oxidized, which intensifies the reaction and improves pulping efficiency.
Application 2: in medicine, alkyl anthraquinones also have significant medicinal value. According to the continuous research at this stage, the antibacterial, anti-inflammatory, anti-virus and killing tumour cells of anthraquinone compounds have been continuously explored, and some have been applied to the actual disease resistance work.
Application 3: in terms of organic synthesis, a synthetic method of 3,3 '- dimethyl-9,9' - biathlete has been developed. The method includes the following steps:
(1) Add 2-Methylanthraquinone, acetic acid, tin particles and concentrated hydrochloric acid into the reaction bottle, stir and cool, pour the reaction solution into water, filter and recrystallize to obtain 3-methyl anthraquinone solid;
(2) Add 3-methylxanthine, acetic acid, metal particles and concentrated hydrochloric acid obtained in step (1) into the reaction bottle, stir the reaction, cool, filter and recrystallize to get 3,3 '- dimethyl-9,9' - biathlete. The metal particles are zinc particles or tin particles, and the molar ratio of 3-methylxanthine to metal is 1 ∶ 3 1 ∶ 10. Note: the invention is mainly used to prepare 3,3 '- dimethyl-9,9' - biathletes.
Synthetic 2-alkyl anthraquinone -- styrene method
The styrene method opens up a new idea for synthesizing alkyl anthraquinone. From a technical point of view, the styrene method is not suitable for raw materials such as anthracene or naphthalene. Still, cheaper and readily available styrene is a significant breakthrough in the synthesis of alkyl anthraquinone. Under acidic conditions, vanadium pentoxide, titanium oxide and antimony trioxide are used as catalysts for oxidation reaction to oxidize and cyclize styrene to produce alkyl indene. In this step, the yield can reach more than 85 percent , then corrupted and dehydrated to obtain 2-methyl anthraquinone
The process also disadvantages harsh conditions, poor selectivity and many by-products, so it has not been industrialized.