2003年6月
Super acid-induced pummerer-type cyclization reaction: Improvement in the synthesis of chiral 1,3-dimethyl-1,2,3,4-tetrahydroisoquinolines
CHEMICAL & PHARMACEUTICAL BULLETIN
- ,
- ,
- ,
- 巻
- 51
- 号
- 6
- 開始ページ
- 667
- 終了ページ
- 672
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- 出版者・発行元
- PHARMACEUTICAL SOC JAPAN
Improved synthesis of four stereoisomeric chiral 1,3-dimethyl-1,2,3,4-tetrahydroisoquinolines (la, b, ent-1a, b) was achieved via the super acid-induced cyclization of chiral N-[1-methyl-2-(phenylsulfinyl)ethyl]-N-(1-phenylethyl)formamides (4a, b, ent-4a, b) using the Pummerer-type cyclization reaction as a key step. The cyclization leading to the isoquinoline ring proceeded in a quantitative manner when trifluoromethane sulfonic acid (TFSA) was used as the super acid, although Friedel-Crafts-type alkylation of 4-phenylsulfanyl TIQ derivatives (5) with benzene used as the solvent accompanied cyclization to yield the 4-phenyl-TIQs (7). The byproduct (7) was exclusively formed when a large excess amount of TFSA was used.
- リンク情報
- ID情報
-
- ISSN : 0009-2363
- Web of Science ID : WOS:000183224700011