Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Process for preparing 2-methyl-1,4-naphthaquinoue using 2-methyl-naphthalene

A technology of methyl naphthalene and methyl naphthylamine, applied in the field of preparing 2-methyl-1, can solve the problems of difficult recovery, high catalyst input cost, equipment corrosion and the like

Inactive Publication Date: 2007-11-14
上海力智生化科技有限公司
View PDF6 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the input cost of the catalyst is high, it is difficult to recycle, and the equipment is severely corroded (WO2002079133)

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Process for preparing 2-methyl-1,4-naphthaquinoue using 2-methyl-naphthalene
  • Process for preparing 2-methyl-1,4-naphthaquinoue using 2-methyl-naphthalene

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] 71g (0.5mol) of 2-methylnaphthalene was dissolved in 200ml of glacial acetic acid, cooled in an ice-water bath, and 50ml of fuming nitric acid was slowly added dropwise, and the dropwise addition was completed in about half an hour. Stir at 5-10° C. for 2 h, and track by TLC until the reaction is complete. Dilute with 750ml of water, extract with 100ml×3 dichloromethane, combine the organic phases, wash with saturated aqueous sodium bicarbonate until neutral, and dry over anhydrous magnesium sulfate. Filter, remove the solvent, and recrystallize with methanol to obtain 70-75 g of 2-methyl-1-nitronaphthalene, yield: 75-80%. mp.80~82℃; 1 HNMR (400MHz, CDCl 3 ): δ2.52(s, 3H), 7.35-7.38(m, 1H), 7.54-7.58(m, 1H), 7.62-7.67(m, 1H), 7.73-7.77(m, 1H), 7.88-7.90 (m,2H)ppm.

Embodiment 2

[0022] Dissolve 36g (0.25mol) of 2-methylnaphthalene in 200ml of dichloroethane, cool in an ice-water bath, add 1ml of concentrated sulfuric acid dropwise, then slowly add 30ml of concentrated nitric acid (content 65% to 68%) dropwise, and the dropwise addition is completed in about 30 minutes . Stir at 5-10° C. for 5 h, and track by TLC until the reaction is complete. Wash with 100 ml of water and 100 ml of saturated aqueous sodium bicarbonate, and dry over anhydrous magnesium sulfate. Filter and remove the solvent to obtain the crude product. After methanol recrystallization, the purity is 99% (HPLC), and the yield is 70-75%.

Embodiment 3

[0024] 48g (0.25mol) of 2-methyl-1-nitronaphthalene was dissolved in 20ml of ethyl acetate, 0.5g of 10% Pd / C catalyst was added, and stirred at room temperature under H2 atmosphere for 3 days. The catalyst was removed by filtration, and the filter cake was washed with a little ethyl acetate. The filtrate was dried over anhydrous magnesium sulfate, and the solvent was removed to obtain 40 g of an oily liquid product, 2-methylnaphthylamine, with a purity of 98% (HPLC), and a yield of 98%.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

This invention relates to a method of using 2 - methylnaphthalene as raw material to prepare 2-methyl-1 naphthaquinone, belongs to chemical engineering technique region. The invention includes nitration, reduction and oxidation reaction three steps. The nitration adopts fuming nitric acid or aqua fortis as nitryl reagent, gain gross product 2-methyl-1-nitronaphthalene; gross product under ordinary pressure takes catalytic hydrogenation by reducing reaction, translated into 2 - methylnaphthalene amine; catalyzer used for hydrogenation is Pd / C; oxidation reaction oxidize above offspring into end product, and the oxidizer is dioxide manganese, hydrogen peroxide and so on. The invention has merits of high oxidative regioselectivity, mild reaction conditions, simple handling and security, high yield and low cost.

Description

technical field [0001] The invention belongs to the technical field of chemical industry, and in particular relates to a new method for preparing 2-methyl-1,4-naphthoquinone by using 2-methylnaphthalene as a raw material. Background technique [0002] 2-Methyl-1,4-naphthoquinone (2-Methyl-1,4-naphthoquinone, abbreviated as 2-MNQ, also known as 2-menaquinone,) is the earliest used vitamin K3 and the key intermediate of synthetic vitamin K body. Its pharmacological activity has aroused widespread interest (Bioorg.Med.Chem.Lett.2002, 12, 2729), can be used as a procoagulant drug (Science 1995, 269, 1684), and participates in the synthesis of prothrombin and coagulation factors in the liver , is also an indispensable feed additive for the growth and development of poultry. [0003] 2-Methyl-1,4-naphthoquinone has a variety of preparation methods, which are roughly divided into two types: direct oxidation method and indirect conversion method: direct oxidation can be obtained b...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C07C50/10C07C46/04
Inventor 桑大永孙猛赵志林文佳
Owner 上海力智生化科技有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com