SU410016A1 - - Google Patents

Description

one

This invention relates to a procedure for the preparation of new compounds, nililogene or thiapiranylidene oxazolones of the general formula

o (: - o

; - N --- "RI A" 7

 X R

where R and R4 are non-substituted, 1 or wen substituted phenyl, R2 and Rs are a hydrogen atom or a pair of substituents Ri-Ra and Rs-R, independently of one another, ground atoms, supplementing the unsubstituted or substituted benzene ring;

X is an oxygen or sulfur atom.

These compounds can serve as intermediates in organic synthesis. On the one hand, using the ability of azlactopes to various types of hydrolysis, alcoholysis, aminolysis, etc., it is possible to synthesize pyranyl and pyranyldehyde derivatives of amino and keto acids, acetic acids, acetopitriles, dipeptides; the latter can be converted to the corresponding pyryl salts. On the other hand, using the ability of the pyrilic ring to recycle, it is possible to obtain amino acids, keto acids, nitriles, etc., with substituents derived from the pyryl cation.

Pyranylidene- or thiapyranylidenoxazolones cannot be obtained by Erlenmeyer reaction by the interaction of pyropes with hippuric acid, as well as other known methods.

The proposed method consists in that the hippuric acid is heated with acetic anhydride, the resulting azlactop is reacted with chlorine substituted pyryl or thiapyryl of the general formula

20

where RI, R2, RS, R4 and X are as defined above, in an aprotic organic solvent such as nitromethane, and the desired product is isolated by conventional means.

Mostly hippuric acid is heated at 104-107 ° C with an excess of acetic anhydride, followed by distilling off the excess of acetic anhydride in a vacuum.

In addition to nitromethane, dimethylformamide, acetonitrile, and chloroform can be used as an aprotic organic solvent.

The desired product precipitated after cooling is separated, washed with alcohol and crystallized from a suitable organic solvent, preferably from dimethylformamide.

The structure of the resulting nirannidene derivatives of oxazoloes has been proven by elementary analysis, IR spectra and some transformations, for example, into the corresponding amino acid derivatives and their esters.

Example 1. 2-Phenyl- (2,6-diphenyls-1-pyridylidene-4) -oxazolone.

2.7 g (0.015 mol) of hippuric acid in 5 ml of acetic anhydride is heated for 10 minutes at 105–107 ° C. Then, the excess anhydride was completely removed in vacuo, 3.67 g (0.01 mol) of 2,6-diphenyl-4-chloropyrily-iherhlorate, 10 ml of dry nitromethane were added to the residue, and the mixture was boiled for 0.5 hour; already in the process of boiling an orange crystalline product is formed. After cooling, the latter is filtered off, washed with cold alcohol and dried. Yield of the desired product 3.0 g (76.7%); m.p. 246 ° C (from dimethylformamide).

Found,%: C 80.05; H 4.43; N 3.67.

SzbPYRz.

Calculated,%: C 79.79; P 4.35; N 3.58.

Example 2. 2-Phenyl-4-flavilidenoxazolone.

3.4 g (0.01 mol) of 4 chloroflaviliy-perchlorate, 10 ml of pitromethane were added to the saturated azlactone obtained from analogous to example I (from 2.7 g of hippuric acid), 10 ml of pitromethane and the reaction mixture was heated for 1 minute in a water bath. The product precipitated after cooling is f.ilted, washed with dry benzene and twice with petroleum ether. The yield of the target product is 3.1 g (84.9%); m.p. 202 ° C (from dimethylformamide).

Found,%: C 79.12; H 4.20; N 4.02.

Ca-iHisNOa.

Calculated,%: C 78.90; H 4.11; N 3.84.

Similarly, azlactoia are obtained from 2,6-diphenyl-4-chlorothiapyrily-perchlorate (81.1%) and 2,6-diphenyl-3-bromo-4-chloropyrily-perchlorine a (lbM).

1. The method of obtaining pyrimylidene- or tiannoradalenoxazole general formula

Claims (2)

1, / - SeN. Cc X R where RI and R-i are unsubstituted or substituted fennl, iRa and .Rs are a hydrogen atom or a pair of substituents RI-R2 and RS-iR.1 independently of each other is a group of atoms that adds to the substitution or substitution of benzene ring; X is an oxygen or sulfur atom, characterized in that the hippuric acid is heated with acetic anhydride, the resulting azlaktoi are reacted with chlorinated salts of pyryl or tapyril of the general formula C1 Rb L 2 Yy © CiOt, L l liif x kj where RI, R2, Rs, RI and X are as defined above, in an aprotopic organic solvent, e.g., nitrometaia, and the desired product is isolated by conventional means. 2. A method according to claim 1, wherein the hippuric acid is heated at 104-107 ° C with an excess of acetic acid, followed by an excess of acetic anhydride.