125289-60-3Relevant articles and documents
F- Nucleophilic-Addition-Induced Allylic Alkylation
Tian, Panpan,Wang, Cheng-Qiang,Cai, Sai-Hu,Song, Shengjin,Ye, Lu,Feng, Chao,Loh, Teck-Peng
, p. 15869 - 15872 (2016)
Herein we present a novel strategy based on palladium-catalyzed allylic alkylation by taking advantage of the nucleophilic addition of external fluoride onto gem-difluoroalkenes as the initiation step. The merit of this protocol is highly appealing, as it enables a formal allylation of trifluoroethylarene derivatives through the in situ generation of β-trifluorocarbanions, which otherwise are deemed to be problematic in deprotonative allylation. Furthermore, this strategy distinguishes itself by high modularity, operational simplicity, and wide substrate scope with respect to allyl carbonates, giving rise to a broad array of homoallyltrifluoromethane derivatives, which otherwise would not be easily obtained using existing synthetic methods.
Sulfinate-Engaged Nucleophilic Addition Induced Allylic Alkylation of Allenoates
Lin, Ling-Zhi,Che, Yuan-Yuan,Bai, Peng-Bo,Feng, Chao
supporting information, p. 7424 - 7429 (2019/10/02)
A strategically novel Pd-catalyzed nucleophilic addition induced allylic alkylation reaction (NAAA) of allenoates has been successfully accomplished. By judiciously integrating ZnCl2-promoted Michael addition with Pd-catalyzed allylic alkylation, allenoates readily undergo allyl-sunfonylation at the internal double bond, thus providing a straightforward avenue for the rapid assembly of a host of structurally diversified α-allyl-β-sufonylbut-3-enoate derivatives. The success of this transformation profits from a delicate control of the reaction kinetic of each elementary step, thanks to the synergistic interaction of Pd/Zn bimetallic system, thus suppressing either direct allylic sulfonylation or premature quenching of therein in situ generated ester enolate intermediate. Furthermore, by expanding the scope of workable Michael acceptor beyond those previously required doubly activated ones, such as methylenemalononitrile, the present work substantially enriches the repertoire of NAAA reactions.
Stereoselective Synthesis of a Highly Oxygenated δ-Lactone Related to the Core Structure of (-)-Enterocin
Wegmann, Marcus,Bach, Thorsten
, p. 209 - 217 (2016/12/24)
The title compound was prepared in a concise route starting from an appropriately protected (S)-glyceraldehyde. A highly diastereoselective (d.r. >95:5) Mukaiyama aldol reaction of an acetoacetate-derived silyl enol ether served as the initial step of the synthetic sequence. It was found that protection of the glyceraldehyde as a butane-2,3-dione acetal is required to achieve the desired diastereoselectivity. Upon lactonization, a Tsuji-Trost allylation and a subsequent one-pot reaction cascade including an ozonolysis and an α-hydroxylation gave diastereoselective access to the desired α-hydroxy-β-oxo-δ-lactone. Alternative synthetic approaches are discussed and proof for the configuration of the product is presented.
Asymmetric Dearomatization/Cyclization Enables Access to Polycyclic Chemotypes
Hayashi, Mikayo,Brown, Lauren E.,Porco, John A.
supporting information, p. 4800 - 4804 (2016/10/13)
Enantioenriched, polycyclic compounds were obtained from a simple acylphloroglucinol scaffold. Highly enantioselective dearomatization was accomplished using a Trost ligand–palladium(0) complex. A computational DFT model was developed to rationalize observed enantioselectivities and revealed a key reactant-ligand hydrogen bonding interaction. Dearomatized products were used in visible light-mediated photocycloadditions and oxidative free radical cyclizations to obtain novel polycyclic chemotypes including tricyclo[4.3.1.01,4]decan-10-ones, bicyclo[3.2.1]octan-8-ones and highly substituted cycloheptanones.
Optimization of asymmetric hydrogenation of 3-phenyl-3-butenoic acid catalyzed by rhodium(I)-4,5-bis-2,2-dimethyldioxolane (DIOP)
Yamamoto, Keiji,Ikeda, Kiyoshi,Yin, Leong Kwai
, p. 319 - 332 (2007/10/02)
Enantioselective, homogeneous hydrogenation of 3-phenyl-3-butenoic acid (1) has extensively been examined in the presence of the rhodium(I)/4,5-bis-2,2-dimethyldioxolane (DIOP) catalyst systems.Optimization of the reaction conditions was undertaken mainly by controlling effects of added tertiary amines as well as solvent polarities on the enantio-selectivity of the product.The best asymmetric yield (85.1percent e.e.) was attained when the hydrogenation was carried out in the presence of triethylamine (5 molpercent) in 75percent aqueous methanol using a neutral rhodium-DIOP catalyst.
