66022-00-2Relevant articles and documents
Ni-Catalyzed Cycloisomerization between 3-Phenoxy Acrylic Acid Derivatives and Alkynes via Intramolecular Cleavage and Formation of the C-O Bond to Give 2,3-Disubstituted Benzofurans
Ohno, Shohei,Qiu, Jiawei,Miyazaki, Ray,Aoyama, Hiroshi,Murai, Kenichi,Hasegawa, Jun-Ya,Arisawa, Mitsuhiro
supporting information, p. 8400 - 8403 (2019/10/14)
Reactions based on transition-metal-catalyzed C-O bond cleavage have attracted much attention as a new synthetic method. Until now, several intermolecular reactions via C-O bond cleavage of aryl ethers, alkenyl ethers, esters, and others have been reported. Here we report an unprecedented C-O bond cleavage of 3-phenoxy acrylic acid derivatives, followed by intramolecular C-O bond formation with alkynes. This reaction gave 2,3-disubstituted benzofurans having useful functional groups-silyl substituents and acrylic acid derivatives- A t the 2- A nd 3-positions, respectively. This report also described theoretical (DFT) insights into the mechanism.
A new method for the preparation of non-terminal alkynes: Application to the total syntheses of tulearin A and C
Lehr, Konrad,Schulthoff, Saskia,Ueda, Yoshihiro,Mariz, Ronaldo,Leseurre, Lucie,Gabor, Barbara,Fürstner, Alois
supporting information, p. 219 - 227 (2015/02/19)
Lactones are known to react with the reagent generated in situ from CCl4 and PPh3 in a Wittig-type fashion to give gem-dichloro-olefin derivatives. Such compounds are now shown to undergo reductive alkylation on treatment with organolithium reagents RLi to furnish acetylene derivatives bearing the substituent R at their termini (R=Me, n-, sec-, tert-alkyl, silyl); the reaction can be catalyzed with either Cu(acac)2 or Fe(acac)3/1,2-diaminobenzene. Two alkynol derivatives prepared in this way from readily accessible lactone precursors served as the key building blocks for the total syntheses of the cytotoxic marine macrolides tulearin A (1) and C (2). The assembly of these fragile targets hinged upon ring closing alkyne metathesis (RCAM) followed by a formal trans-reduction of the resulting cycloalkynes via trans-hydrosilylation/protodesilylation.
An intra/intermolecular suzuki sequence to benzopyridyloxepines containing geometrically pure exocyclic tetrasubstituted alkenes
Carson, Matthew W.,Giese, Matthew W.,Coghlan, Michael J.
supporting information; experimental part, p. 2701 - 2704 (2009/05/26)
(Chemical Equation Presented) A route to enable the preparation of 5-benzylidenyl-benzopyridyloxepine analogues was developed to continue our research in the field of nuclear hormone receptor modulators. The key steps are1) a syn-stereoselective diboratio
