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[摘要]：1-(2-Aminoaryl)-2-yn-1-ols, easily obtained by the Grignard reaction between 1-(2-aminoaryl)ketones and alkynylmagnesium bromides, were subjected to carbonylative conditions in the presence of the PdI2-KI catalytic system, in the presence and in the absence of an external oxidant. Under oxidative conditions (80 atm of a 4:1 mixt. of CO-air, in MeOH as the solvent at 100 癈 and in the presence of 2 mol% of PdI2 and 20 mol% of KI), 1-(2-aminoaryl)-2-yn-1-ols bearing a primary amino group were selectively converted into quinoline-3-carboxylic esters in fair to good yields [45-70%, based on starting 1-(2-aminoaryl)ketones], ensuing from 6-endo-dig cyclization followed by dehydration and oxidative methoxycarbonylation. On the other hand, indol-2-acetic esters, deriving from 5-exo-dig cyclization followed by dehydrating methoxycarbonylation, were selectively obtained in moderate to good yields [42-88%, based on starting 1-(2-aminoaryl)ketones] under nonoxidative conditions (90 atm of CO, in MeOH as the solvent at 100 癈 and in the presence of 2 mol% of PdI2 and 20 mol% of KI), in the case of 1-(2-aminoaryl)-2-yn-1-ols bearing either a primary or secondary amino group and substituted with a bulky group on the triple bond. |
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