825-31-0Relevant articles and documents
Highly Enantioselective, Organocatalytic, and Scalable Synthesis of a Rare cis,cis-Tricyclic Diterpenoid
Townsend, Daniel,Shankland, Kenneth,Weymouth-Wilson, Alex,Komsta, Zofia,Evans, Tim,Cobb, Alexander J. A.
supporting information, p. 3504 - 3508 (2020/03/05)
A highly enantioselective, organocatalytic, and scalable synthesis of a very unusual cis-decalin-cis-hydrindane tricyclic diterpenoid system has been achieved. Despite the prevalent pharmacological space that the related trans,trans and trans,cis-systems occupy, there have been no reports of an asymmetric synthesis of the cis,cis systems in the literature until now. We demonstrate the flexibility of our approach not only through access to a diverse range of products, all of which are attained in exceptionally high selectivities, but also by showing their easy conversion to the corresponding trans,cis-system and other derivatives.
Forging Fluorine-Containing Quaternary Stereocenters by a Light-Driven Organocatalytic Aldol Desymmetrization Process
Cuadros, Sara,Dell'Amico, Luca,Melchiorre, Paolo
supporting information, p. 11875 - 11879 (2017/09/20)
Reported herein is a light-triggered organocatalytic strategy for the desymmetrization of achiral 2-fluoro-substituted cyclopentane-1,3-diketones. The chemistry is based on an intermolecular aldol reaction of photochemically generated hydroxy-o-quinodimethanes and simultaneously forges two adjacent fully substituted carbon stereocenters, with one bearing a stereogenic carbon–fluorine unit. The method uses readily available substrates, a simple chiral organocatalyst, and mild reaction conditions to afford an array of highly functionalized chiral 2-fluoro-3-hydroxycyclopentanones.
Synergistic Catalysis: Metal/Proton-Catalyzed Cyclization of Alkynones Toward Bicyclo[3.n.1]alkanones
Zhu, Shifa,Zhang, Qiaohui,Chen, Kai,Jiang, Huanfeng
supporting information, p. 9414 - 9418 (2015/08/06)
A highly efficient and practical synergistically metal/proton-catalyzed Conia-ene reaction for the synthesis of bicyclo[3.n.1]alkanones has been developed. This synergistic catalysis was successfully utilized in modifying natural compounds such as methyl dihydrojasmonate, α,β-thujone, and 5α-cholestan-3-one. Furthermore, the bridged carbonyl group of bicyclo[3.2.1]alkanones could be easily attacked by nucleophiles to give the ring-opened cycloheptenone products or bicyclo[4.2.1]amide in excellent yields. These reactions provide rapid access to a diverse range of cyclic structures from simple starting materials or naturally occurring compounds. A highly efficient and practical synergistically metal/proton-catalyzed Conia-ene reaction for the synthesis of bicyclo[3.n.1]alkanones has been developed. The reaction was successfully utilized in modifying natural compounds such as methyl dihydrojasmonate, α,β-thujone, and 5α-cholestan-3-one. Furthermore, the bicyclo[3.2.1]alkanones can be ring-opened by nucleophiles to give the corresponding products in excellent yields.
Direct amino acid-catalyzed cascade biomimetic reductive alkylations: Application to the asymmetric synthesis of Hajos-Parrish ketone analogues
Ramachary, Dhevalapally B.,Kishor, Mamillapalli
supporting information; experimental part, p. 4176 - 4187 (2009/02/07)
A direct amino acid-catalyzed chemo- and enantioselective process for the double cascade synthesis of highly substituted 2-alkyl-cyclopentane-1,3-diones, 2-alkyl-3-methoxy-cyclopent-2-enones and Hajos-Parrish (H-P) ketone analogs is presented via reductive alkylation chemistry. For the first time, we have developed a single-step alkylation of cyclopentane-1,3-dione with aldehydes/ketones and a Hantzsch ester through an organocatalytic reductive alkylation strategy. A direct combination of amino acid-catalyzed cascade olefination-hydrogenation and cascade Robinson annulations of cyclopentane-1,3-dione, aldehydes/ketones, a Hantzsch ester and methyl vinyl ketone furnished the highly functionalized H-P ketone analogues in good to high yields and with excellent enantioselectivities. Many of the reductive alkylation products have shown direct applications in pharmaceutical chemistry.
Reaction of Aliphatic Dicarboxylic Acids with Acyl Chlorides in the Presence of Aluminum Chloride
Matoba, Katsuhide,Tachi, Masashi,Itooka, Toshiyuki,Yamazaki, Takao
, p. 2007 - 2012 (2007/10/02)
The treatment of succinic acid with lauroyl or stearoyl chloride gave the five-membered β-diketone (II) substituted with a long chain at the α-position, together with a trimer (III) of the acyl chloride.Bicyclononane-2,4-dione (VI) substituted with a methyl or ethyl group at the C3-position was prepared from cyclohexane-1,3-dicarboxylic acid (V) and propionyl or butyryl chloride, respectively.D-Camphoric acid afforded an unexpected product, 4-acyl-2,2,3-trimethyl-3-cyclopentenecarboxylic acid (IX), on reaction with acyl chloride.Although acetyl chloride gave no product on treatment with succinic acid, it afforded 3-acetylbicyclooctane-2,4-dione (XI), 3-acetylbicyclononane-2,4-dione (VId), and 2-acetylcyclohexane-1,3-dione (XII) on reaction with the corresponding dicarboxylic acids.Keywords - β-diketone; cyclic β-diketone; bicyclic β-diketone; dicarboxylic acid; aluminum chloride; acyl chloride; bicycloalkane-2,4-dione
