6,7-dialkoxy-3,4-dihydroisoquinolin-8-ol, process for preparation thereof and process for preparation of 6,7-dialkoxy-1,2,3,4-tetrahydroisoquinolin-8-ol using the compound

摘要

This invention relates to novel 6, 7 - dialkoxy - 3, 4 - dihydroisoquinolin - 8 - ols, a process for preparing the 6, 7 - dialkoxy - 3, 4 - dihydroisoquinolin - 8 - ols reioselectively and in a high yield utilizing the Bischler - Napieralski reaction, a process for synthesizing 6, 7 - dialkoxy - 1, 2, 3, 4 - tetrahydroisoquinolin - 8 - ols via the compounds, and use of the 6, 7 - dialkoxy - 3, 4 - dihydroisoquinolin - 8 - ols for preparation of the 6, 7 - dialkoxy - 1, 2, 3, 4 - tetrahydroisoquinolin - 8 - ols.. It is possible, according to this invention, to obtain the 6, 7 - dialkoxy - 1, 2, 3, 4 - tetrahydroisoquinolin - 8 - ols, which have hitherto been difficult to synthesize, via the 6, 7 - dialkoxy - 3, 4 - dihydroisoquinolin - 8 - ols in a high yield.