105279-16-1Relevant articles and documents
Pd/C-mediated synthesis of (Z)-3-alkylidenephthalides of potential pharmacological interest
Rambabu,Kumar, G. Pavan,Kumar, Barange Deepak,Kapavarapu, Ravikumar,Rao, M.V. Basaveswara,Pal, Manojit
, p. 2989 - 2995 (2013)
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.
Regio- and Stereoselective Synthesis of (Z)-3-Ylidenephthalides via H3PMo12O40-Catalyzed Cyclization of 2-Acylbenzoic Acids with Benzylic Alcohols
Yang, Guoping,Li, Ke,Lin, Xiaoling,Li, Yijin,Cui, Chengxing,Li, Shixiong,Cheng, Yuanyuan,Liu, Yufeng
, p. 3017 - 3022 (2021/09/13)
We report an exclusively tandem C—O and C—C bond forming beyond the esterification and cyclization reaction of 2-acylbenzoic acids with alcohols to regio- and stereoselective synthesis of the (Z)-3-ylidenephthalides. The reaction uses the nontoxic, inexpensive H3PMo12O40 as catalyst and produces water as the sole by-product, making the reaction environmentally benign and sustainable. Moreover, this reaction features an eco-friendly reaction condition, facile scalability, and easy derivatization of the products to drugs and bioactive compounds. The mechanism studies and density functional theory calculations reveal that the appropriate acid catalyst is the key to the selectivity of this transformation.
Ag2O nanoparticle-catalyzed substrate-controlled regioselectivities: direct access to 3-ylidenephthalides and isocoumarins
Chaudhary, Sandeep,Shyamlal, Bharti Rajesh K.,Yadav, Lalit,Tiwari, Mohit K.,Kumar, Krishan
, p. 23152 - 23162 (2018/07/10)
Herein, we disclose the first example of an efficient, silver oxide nanoparticle-catalyzed, direct regioselective synthesis of 3-ylidenephthalides 11-16 and isocoumarins 17-20via sonogashira type coupling followed by substrate-controlled 5-exo-dig or 6-endo-dig cyclization reaction, respectively. This one pot coupling involves reaction of substituted 2-halobenzoic acid with meta/para-substituted and ortho-substituted terminal alkynes, which proceeded in a regioselective manner resulting in the formation of 3-ylidenephthalides or isocoumarins, respectively, in excellent yields (up to 95%) with complete Z-selectivity. This protocol features relatively broad substrate scope, mild conditions, operational simplicity, and is favourable with aromatic/alicyclic terminal alkynes. The competition experiments and gram-scale synthesis further highlight the importance and versatility of the methodology. The proposed mechanistic pathways illustrate that the regioselectivity is substantially being controlled by the substituent(s) present on the acetylenic phenyl ring.
