1-位に第三級アルキル基を有するイソヒノリン類の合成

抄録

Nine new 1-tert-alkyl-6, 7-methylenedioxy-3-methylisoquinolines were synthesized by treating α-3, 4-methylenedioxyphenyl-α-methoxyisopropylamide of tri-substituted acetic acid with phosphoryl chloride by the Rosenmund-Mannich reaction. Xylene was found to be the solvent of choice. The ring-closure was more difficult than in the usual cases and under milder conditions-benzene or toluene as a solvent and shorter heating time- oxazolines were obtained exclusively or chiefly together with some isoquinolines. These oxazolines were converted into the corresponding isoquinolines by heating with POCl₃- xylene, so the former can be regarded as the intermediate of the latter. The yield of isoquinoline decreases with the increase of the molecular weight of the tertiary alkyl group and thus 1-triisoamylisoquinoline could not be synthesized by the present method. Pharmacological properties of these isoquinolines are now being examined.