A practical synthesis of an anthracyclinone synthon
Keyword(s):
One Pot
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The important intermediate 2-acetyl-5,8-dimethoxytetralin (8) in the syntheses of anthracycline antitumor drugs is easily prepared in high yield on a large scale. Conversion of 2,4-pentanedione to 3-(2,5-dimethoxybenzyl)-hex-5-en-2-one (9) was carried out in a three-step, one-pot process by C-alkylating it with 2,5-dimethoxybenzyl bromide, then allyl bromide followed by a retro-Claisen condensation. Conversion of 9 to the tetralin (8) was done first by ozonolysis to the aldehyde (10) followed by cyclization and reduction of the latter by trimethylsilane in trifluoracetic acid – acetone.
Keyword(s):
2018 ◽
Vol 15
(4)
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pp. 572-575
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