Verfahren zur Herstellung substituierter Tetrahydroisochinoline

Compounds of formula wherein the benzenoid rings may be further substituted, the symbols R, which may have the same or different meanings, represent hydrogen atoms or alkyl or aralkyl groups, R1 is an aliphatic, araliphatic or aromatic hydrocarbon group, and R4 is a hydrogen atom or an acyl or alkoxycarbonyl group, are prepared by reaction of 3,4-tetrahydroisoquinoline with a ketone of formula CH2=CHCOR1 in the presence of an alcohol with simultaneous or subsequent addition of a compound of formula R6CHRCOC(R)2R5, wherein R5 is a hydrogen atom or a carboxyl group and R6 is a carboxyl, alkoxycarbonyl or acyl group. Benzenoid substituents specified are aliphatic, araliphatic and aromatic hydrocarbon, ether, thioether and methylenedioxo groups. Examples disclose the preparation of the compound of formula which may be crystallized as its hydrochloride or sulphate, is either the de-form or the mesoform, depending on the proportions of acid. 3 - Acetyl - 1,2,3,4,6,7 - hexahydro - 2 - hydroxy9,10 - dimethoxy - 2 - [1,2,3,4 - tetrahydro - 6,7 -dimethoxy - 2 - (3 - oxobutyl) - isoquinol - 1 - ylmethyl] -11b[H] - benzo - [a] - quinolizine hydrochloride is obtained by treating the abovementioned product of the examples with sodium and alcoholic hydrochloric acid.