IL26949A - 3-nitro-4-halophenol derivatives and their preparation - Google Patents

Description

nitVin derivatives and preparation present invention provides new halophenol derivatives of the general formula in which E is or alkyl and X is The new compounds of X according to the invention are novel and useful as intermediates for the preparation for which possess useful medical activities such as an anesthetic and antiemetic The present invention also provides a process for he the preparation of the derivatives of formula I which comprises reacting derivatives having the general formula II in E is or alkyl and X is with nitrous acid o with a metal nitrite in the presence of an acid and by treating the resulting salts of the alkyl group are pentyl etc As the acid referred to herein there preferably used an organic such as acetic or an aqueous solution of a mineral such as hydrochloric chloric sodium dihydrogen sulfuric examples of metallic nitrites referred to herein are mentioned sodium potassium magnesium calcium barium nickel copper mercury silver The diazonium sal obtained in the reaction may be directly decomposed being isolated from the reaction w water to yield the desired compound of formula Alternatively the diazonium salt may be isolated from the action mixture at low or converted to other and decomposed with water to yield the compound Γ in a subsequent reaction It is generally preferable to decompose diazonium salt with under warming or The following example serve to illustrate the Into a cooled mixture o 40 of concentrated sulfuric acid and 6 of sodium a solution of 1 g of in 185 ml of glacial acetic acid was added dropwise with stirring and the mixture x tained at a temperature lower than The mixture was stirred for one further and was then decomposed with luted sulfuric acid prepared from 80 ml of concentrated furic acid and ml of The reaction mixture was heated with stirring for 1 hour in an oil bath at and was left was poured into ice water and the crystals which formed thereupon were separated suction crystals were washed with ice water and dried to yield g crude of yield was recrystallized from and purified crystals were obtained as faint yellow Calculated for H Gl G S insufficientOCRQuality

Claims (1)

1. 4 derivatives of the general formula OH in which R is or and is A process for the preparation of halophenol derivatives according to Claim 1 which comprises reacting a derivative having the in which R is or l and X is a halogen with nitrous acid with a metal nitrite in the presence of an and treating the thus obtained salt with insufficientOCRQuality