Process for preparing (1-acylaminomethyl)-1,2,3,4-tetrahydroisoquinolines

Abstract

Novel tetrahydroquinolines of the formula ##STR1## wherein R is cycloalkyl or cycloalkenyl each containing 4-7 ring carbon atoms and the cycloalkyl optionally being substituted by one of methyl, hydroxyl or oxo; phenyl substituted by 1-2 of amino, acylamino of up to 4 carbon atoms, Hal, hydroxyl, methoxy or nitro, wherein Hal is fluorine, chlorine, bromine or iodine; thienyl; pyridyl; tetrahydropyranyl; tetrahydrothiopyranyl; and when at least one of R.sup.2, R.sup.3, R.sup.4, R.sup.5 or R.sup.6 is other than H, also phenyl; R.sup.2, R.sup.3 and R.sup.4 each are H or methyl; R.sup.5 and R.sup.6 each are H, methyl or methoxy; R.sup.7 is H or --CO--CH.sub.2 --X wherein X is chlorine, bromine or iodine; the acid addition salts thereof; which compounds are useful as antihelmintics and as intermediates for the production of 2-acyl-4-oxo-1,2,3,6,7,11b-hexahydro-4H-pyrazino-[2,1-a]isoquinoline derivatives; and the corresponding compounds wherein R is alkyl of 1-6 carbon atoms, phenyl substituted by three of the substituents named above, and phenyl when all of R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are H; are produced by acylating the corresponding 1-aminomethyl-1,2,3,4-tetrahydroisoquinoline wherein R.sup.7 is H, and optionally thereafter reducing the R group and/or reacting the ring nitrogen atom with an acylating group.