Synthesis of phthalides through palladium-catalysed heteroannulation of acetylenic compounds
作者:Nitya G. Kundu、Manojit Pal
DOI:10.1039/c39930000086
日期:——
The reaction of o-iodobenzoic acid with various acetylenic compounds in the presence of a palladium catalyst leads to phthalides [1-(3H)isobenzofuran-3-ones] as major products and isocoumarins as minor products.
Palladium-catalysed heteroannulation with terminal alkynes: synthesis of phthalides 1
作者:Nitya G. Kundu、Manojit Pal、Bidisha Nandi
DOI:10.1039/a705450e
日期:——
The palladium–copper-catalysed heteroannulation of o-iodobenzoic acid 3 with terminal alkynes 4–18 leads to the synthesis of (Z)-3-alkylidenephthalides 19–33 as the major products. In certain cases, the formation of isocoumarins 34–37 is also observed.
Aryl iodine-catalysed divergent synthesis of isobenzofuranones and isocoumarins <i>via</i> oxidative 1,2-aryl migration/elimination
作者:Jiaxin He、Jingran Zhang、Xuemin Li、Haofeng Shi、Yunfei Du
DOI:10.1039/d2cc03101a
日期:——
The divergent synthesis of isobenzofuranones and isocoumarins was realized from the reaction of 2-alkenyl benzoic acids and mCPBA in the presence of catalytic aryl iodine and (±)-10-camphorsulfonic acid (CSA). The organocatalytic oxidative reaction is assumed to undergo a cascade process involving lactonization, 1,2-aryl migration and elimination enabled by a modified Koser reagent generated in situ
Regioselective One-Pot Synthesis of Isocoumarins and Phthalides from 2-Iodobenzoic Acids and Alkynes by Temperature Control
作者:Manian Rajesh Kumar、Francis Mariaraj Irudayanathan、Joong Ho Moon、Sunwoo Lee
DOI:10.1002/adsc.201300561
日期:2013.11.11
AbstractCopper‐catalyzed coupling reaction of 2‐iodobenzoic acids and alkynes such as terminal acetylenes, alkynyl carboxylic acids, and trimethylsilylacetylene selectively afforded isocoumarins and phthalides in the presence of cesium carbonate (Cs2CO3) and dimethyl sulfoxide (DMSO). Among the regioselective products, only the 6‐endo‐dig product, isocoumarin, was formed at 100 °C, and the 5‐exo‐dig product, phthalide, was formed as a major product at 25 °C. A variety of alkynes produced the corresponding isocoumarins and phthalides in good yields. A mechanism is suggested in which the formation of 2‐alkynylbenzoic acid as an intermediate via Sonogashira‐type coupling was ruled out in the reaction pathway.magnified image
Pd/C-mediated synthesis of (Z)-3-alkylidenephthalides of potential pharmacological interest
作者:D. Rambabu、G. Pavan Kumar、Barange Deepak Kumar、Ravikumar Kapavarapu、M.V. Basaveswara Rao、Manojit Pal
DOI:10.1016/j.tetlet.2013.03.121
日期:2013.6
The coupling of o-bromobenzoic acid with terminal alkynes using 10% Pd/C-Et3N-CuI-PPh3 as a catalyst system leads to the synthesis of (Z)-3-alkylidenephthalides as the major product along with the traces of isocoumarin when the reaction was performed in 1,4-dioxane. The methodology afforded a range of compounds including (Z)-3-(4-(methylsulfonyl)benzylidene)isobenzofuran-1(3H)-one of potential pharmacological interest. (C) 2013 Elsevier Ltd. All rights reserved.