SU950720A1 - Process for producing 4-carboxy-2,2,5,5-tetramethyl-3-imidazoline-1-oxyl - Google Patents

Description

The invention relates to a process for the preparation of a new stable nitroxyl radical — 4.-carboxy2, 2,5,5-tetramethyl-3-imidazolin-1-oxyl of the formula:

soon

four

HjC.F

OHj CH3

Hjc

(one)

Spin-labeled, carboxylic acids are the starting compounds for the synthesis of spin-labeled acylating agents, the use of which allows the introduction of a spin label into a biological molecule and therefore finds wide application in molecular biology. In addition, the nitroxyl radical of formula (I) is capable of forming chelate complexes with transition metal ions and can be used as a chelating compound with a co-oxidation of the radical center to determine the concentrations of these metaplates by the EPR method. In addition, based on the compound (4-p-dicarbonyl compounds can be synthesized - derivatives 3, -imidazo-

lin-1-oxyl - anoshogi widely known analytical reagents, including a spin label.

A method of obtaining the sodium salt of 4-carboxy-2,2,5,5-tetramethyl-3-imidazolin-1-oxyl of the formula (1) by alkaline hydrolysis of 4-carboxamido-2, 2,5,5-tetramethyl-3-imidazoline- 1-oxyl flj.

The disadvantage of this method is the inaccessibility of the starting 4-carboxamido-2,2,5,5-tetramethyl-3-imidazolin-1-oxyl, obtained either by multistage synthesis, or using poisonous (KCN) or unstable compounds 2 with a low yield (24%) .

There is also known a method for preparing 4-carboxy-2,2,5,5-tetramethyl-3-imidazolin-1-oxyl of formula (1) as a sodium salt by reacting 4-FORMIL-2,2,5,5-tetramethyl-3 -imidazolin-1-oxyl with aqueous-alcoholic alkali at room temperature while blowing air for 15 h 3.

Claims (4)

The disadvantage of this method is the multistage production of 1 initial aldehyde f4, as well as the requirement of its high purity for repl. high yield of the final product (sodium salt of the compound of formula (1)). The aim of the invention is a new method for the preparation of a novel 4-carb10XI-2, 2.5, 5-tetramwt-yl-3-imidazolin-1-oxyl of formula (1) with valuable properties. The goal is achieved by the fact that according to the method for preparing the compound of formula (1), 4-dichloromethyl-2, 2,5,5-tetramethyl-3-imidazolin-1-oxyl is subjected to hydrolysis in aqueous-alcoholic alkali, followed by neutralization with mineral acid and isolation of target product. The starting 4-dichloromethyl-2,2,5,5 tetramethyl-3-imidazolin-1-oxyl is obtained by the interaction of N-chlorosuccinimide with 2,2,4,5,5-pentamethyl-3-imidazoline-1-oxyl: tgan o Sysanonon-CKjCooHSll cHjCcimoH -Rci S ate, from,, CH, CHj K yJ -, s (-yf H Njf B Bee stages flow in high yields, do not require hard-to-reach raw materials, are simple in the performance of f4 EXAMPLE 1, 4-Carboxy2, 2,5,5-tetramethyl-3-imidazolin 1-oxyl. To a solution of 0.3 g of NaOH in 1.5 MP of water and 15 ml of alcohol, while stirring at room temperature, add 0.56 g of 4-dichloromethyl 2, 2.5 , 5-tetramethyl-3-imidazolin-1-oxyl. After complete dissolution of The solution is distilled at room temperature for 15–20 hours. The alcohol is distilled off, 5 ml of water are added to the residue, washed several times with chloroform, and the shaped solution is discarded. The aqueous solution is acidified with hydrochloric acid to pH 1- 2, extracted with chloroform, the extract was dried with CHgS04), filtered off, and the chloroform was distilled off to obtain O, 28 g (60%) of compound (1). T. pl. 117-118s. Found,%: C 51.7; H 6.7; N 15.0. . Calculated,%: C 51.9 N 7.0-, N 15.1. Thus, the proposed spasob makes it possible to use available raw materials and with a high yield of half a kilo rate the target product of the formula T), which can be widely used both in analytical chemistry and in molecular biology. The claims of the method for producing 4-carboxy2, 2,5,5-tetramethyl-3-imidazolin-1-oxyl of the formula COOH HjCj, CH (), characterized in that 4-dichloromethyl-2,2,5,5-tetramethyl-3-imidazoline-1- oxyl is subjected to hydrolysis in aqueous-alcoholic alkali, followed by neutralization with mineral acid and separation of the target product. Sources of information taken into account during the examination 1. USSR author's certificate No. 282330, cl. From 07 d 49/36, 1969. 2. Grigoriev, I.D., Schukin, G.I., Druganov A. -.T, and Volodarsky, L. B. Obtaining and properties of derivatives of aldehydes and ketones of 3-imidazoline containing a nitroxyl radical center. Izv. SB AS USSR. Ser. Chemical Sciences, 1979, № 2/1, p. 80-87. 3. Grigoriev I.A. and Volodarsky L.V. Participation of the nitroxyl radical in the oxidation of the aldehyde and alcohol groups in 3-imidazolyl-oxyls. Izv. Academy of Sciences of the USSR. Ser. Khi1978, № 1, p. 208-210. 4. USSR author's certificate No. 420627, cl. C 07 d 49/34, 1971.