Hoechst Celanese Corporation

Joseph A McDonough

Ahmed M Tafesh

Olan S Fruchey

Graham N Mott

B Frank Wood

Richard Vicari

Mohammad Aslam

George Kvakovszky

Kathleen Nelson Juneau

Debasish Kuila

Ahamed M Tafesh

Charles H Brown, Ii

Ibrahim M Uwaydah

Sharon R Fitzhenry

The present invention provides processes which are flexible, cost effective, and commercially viable methods of manufacturing or producing products from 2-hydroxyacetophenone (2-HAP). Of particular interest of the available products are 4-hydroxycoumarin, warfarin-alkali salt, preferably warfarin sodium and warfarin-alkali salt-isopropyl alcohol (2-propanol) complex, more preferably warfarin-sodium-isopropyl alcohol complex. As is known, these compounds are useful as vitamin K dependent anticoagulants in the treatment of humans and animals. In different doses, they are also useful as rodenticide. The inventive process involves contacting 2-HAP, carbonate ester and effective base followed by treatment with an unsaturated ketone and phase transfer catalyst to ultimately yield product.

Syntheses based on 2-hydroxyacetophenone

The present invention provides novel substituted pyrazines or pyrazine derivatives ('NPD') which are functional and have useful application as a monomer for a variety of high performance polymers such as polyester, polyarylate, polycarbonate, polyetherketones, epoxides, polyimides, polyamides, and polyamides-imides. These NPD have the general formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are defined herein.

Substituted pyrazines

An arylisonitrosoalkanone is hydrogenated in the presence of a noble metal catalyst and a weak carboxylic acid to form an arylalkanolamine which is then hydrogenated in the presence of a strong mineral acid and the transition metal catalyst to form an arylalkylamine. When the arylisonitrosoalkanone is an isonitrosoacetophenone, the isonitrosoacetophenone is prepared by one of two methods. In the first method, a substituted or an unsubstituted isonitrosoacetophenone is prepared from a corresponding substituted or unsubstituted acetophenone by oxidizing the acetophenone to form a substituted or an unsubstituted phenylglyoxalacetal in a reactor, hydrolyzing the phenylglyoxal acetal in the same reactor to form a corresponding substituted or unsubstituted phenylglyoxal, and condensing the phenylglyoxal with hydroxylamine or a salt thereof in the same reactor to form the substituted or unsubstituted isonitrosoacetophenone. Alternatively, the substituted or unsubstituted isonitrosoacetophenone is prepared from the corresponding substituted or unsubstituted acetophenone by reacting the substituted or unsubstituted acetophenone in water with a source of a nitrosonium ion in the presence of a strong acid to form a corresponding substituted or unsubstituted phenylglyoxal, and condensing the phenylglyoxal with hydroxylamine or a salt thereof to form the substituted or unsubstituted isonitrosoacetophenone. In either method, any strong acid that might be present in the reaction mass following the condensation to the isonitrosoacetophenone shall be removed therefrom prior to initiating the hydrogenation of the isonitrosoacetophenone to the arylalkanolamine.

Process for preparing substituted and unsubstituted arylalkylamines

This invention provides a process for directly preparing arylethylamines and their salts from (.alpha.-halo-.alpha.-oximino)acetophenones. The process involves hydrogenation in presence of a transition metal catalyst. The process is illustrated by conversion of 4-hydroxy-(.alpha.-chloro-.alpha.-oximino)acetophenone to Tyramine hydrochloride: ##STR1##

Process for the preparation of arylethylamines and substituted

This invention provides a process for directly preparing hydrohalide salts of arylethylamines from (.alpha.-chloro-.alpha.-oximino)acetophenones. The process involves hydrogenation in presence of a transition metal catalyst in an organic acid in substantial absence of moisture. The process is illustrated by conversion of 4-hydroxy (.alpha.-chloro-.alpha.-oximino)acetophenone to Tyramine hydrochloride: ##STR1##

Arylalkylamines (as the hydrochloride salt), e.g. tyramine hydrochloride, are prepared by hydrogenating substituted or unsubstituted aryl-.alpha.-oximinoalkyl ketones, e.g. p-hydroxyisonitroacetophenone, in either in an aqueous reaction medium comprising hydrochloric acid, essentially without the presence of a lower alkyl alcohol in said reaction medium, or in an aqueous reaction medium comprising water, hydrochloric acid, and a lower alkyl alcohol, wherein the alcohol comprises less than about 90% by volume of the reaction medium. A substituent on the aryl portion of the aryl-.alpha.-oximinoalkyl ketone must be on a position which activates the aromatic ring.

Growing community of inventors

Corpus Christi, TX, United States of America

Joseph A McDonough