24257-93-0Relevant articles and documents
Synthesis of 4,5-Benzotropones by Cyclization of 1,3-Bis-Silyl Enol Ethers with 1,2-Dialdehydes
Albrecht, Uwe,Van Nguyen, Thi Hong,Langer, Peter
, p. 3417 - 3424 (2004)
The cyclization of 1,3-bis-silyl enol ethers or (2,4 -dioxobutylidene)triphenylphosphoranes with phthalic dialdehyde allowed a convenient synthesis of a variety of 4,5-benzotropones. The hydrogenation of benzotropones afforded functionalized benzocycloheptanones which were transformed into tricyclic butenolides.
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
supporting information, 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.
Enantioselective Synthesis of 6,6-Disubstituted Pentafulvenes Containing a Chiral Pendant Hydroxy Group
Nouch, Ryan,Cini, Melchior,Magre, Marc,Abid, Mohammed,Diéguez, Montserrat,Pàmies, Oscar,Woodward, Simon,Lewis, William
, p. 17195 - 17198 (2017/11/27)
Simple enantioselective synthesis of 6,6-disubstituted pentafulvenes bearing chiral pendant hydroxy groups are attained by cascade reactivity using commercially available proline-based organocatalysts. Condensation of cyclopentadiene with the acetyl function of a 1,2-formylacetophenone, followed by cyclization of a resulting fulvene-stabilized carbanion with the formyl group, generates bicyclic chiral alcohols with initial er values up to 94:6. Exceptional enantio-enrichment of the resultant alcohols results upon crystallization—even near racemic samples spontaneously de-racemize. This enables new families of substituted cyclopentadienes that are both enantiomerically and diastereomerically pure to be rapidly attained.
