TY - DATA T1 - Synthesis of Phthalides and 3,4-Dihydroisocoumarins Using the Palladium-Catalyzed Intramolecular Benzannulation Strategy PY - 2002/03/22 AU - Taishi Kawasaki AU - Shinichi Saito AU - Yoshinori Yamamoto UR - https://acs.figshare.com/articles/journal_contribution/Synthesis_of_Phthalides_and_3_4-Dihydroisocoumarins_Using_the_Palladium-Catalyzed_Intramolecular_Benzannulation_Strategy/3692817 DO - 10.1021/jo016336o.s001 L4 - https://ndownloader.figshare.com/files/5783178 KW - formation KW - Strategy KW - intramolecular KW - Benzannulation KW - eq KW - regioisomeric products B KW - enyne KW - synthesis KW - benzannulation reaction KW - Dihydroisocoumarin KW - Various kinds KW - ring compounds KW - phthalides 9 KW - yield KW - Phthalide KW - Intramolecular KW - novel method KW - methodology KW - butylphthalide 23 KW - dihydroisocoumarin KW - Synthesi KW - chemoselectively N2 - A novel method for the synthesis of phthalides and 3,4-dihydroisocoumarins via the palladium-catalyzed intramolecular benzannulation of bis-enyne and enyne−diyne systems is described. Various kinds of substituted phthalides 9 and 17 and 3,4-dihydroisocoumarins 19 were synthesized from 8, 16, and 18, respectively, in moderate to excellent yields. The benzannulation reaction proceeded chemoselectively to give the corresponding fused ring compounds A without the formation of the regioisomeric products B (eq 6). Furthermore, this methodology was applied to the synthesis of biologically active 3-n-butylphthalide 23. ER -